Remove to_cstring() naming convention ambiguity

Add a trait for str.strdup() to replace to_cstring() which avoid the signature ambiguity with .to_string(). Also instruduce CString::yolo() as a shortcut to CString::new().unwrap() and use it whenever the variable does can be deallocated by going out of scope. This is less error prone. Use some Path.to_c_string() functions where possible.
2026-04-29 03:16:29 +03:00 · 2019-08-01 00:08:23 +02:00
parent e7428887d0
commit b6b0849bce
31 changed files with 395 additions and 381 deletions
--- a/src/chatlist.rs
+++ b/src/chatlist.rs
@@ -256,7 +256,7 @@ impl<'a> Chatlist<'a> {

        let mut ret = dc_lot_new();
        if index >= self.ids.len() {
-            (*ret).text2 = to_cstring("ErrBadChatlistIndex");
+            (*ret).text2 = "ErrBadChatlistIndex".strdup();
            return ret;
        }

@@ -267,7 +267,7 @@ impl<'a> Chatlist<'a> {
            chat = dc_chat_new(self.context);
            let chat_to_delete = chat;
            if !dc_chat_load_from_db(chat, self.ids[index].0) {
-                (*ret).text2 = to_cstring("ErrCannotReadChat");
+                (*ret).text2 = "ErrCannotReadChat".strdup();
                dc_chat_unref(chat_to_delete);

                return ret;
@@ -293,7 +293,7 @@ impl<'a> Chatlist<'a> {
        if (*chat).id == DC_CHAT_ID_ARCHIVED_LINK as u32 {
            (*ret).text2 = dc_strdup(0 as *const libc::c_char)
        } else if lastmsg.is_null() || (*lastmsg).from_id == DC_CONTACT_ID_SELF as u32 {
-            (*ret).text2 = to_cstring(self.context.stock_str(StockMessage::NoMessages));
+            (*ret).text2 = self.context.stock_str(StockMessage::NoMessages).strdup();
        } else {
            dc_lot_fill(ret, lastmsg, chat, lastcontact, self.context);
        }
--- a/src/config.rs
+++ b/src/config.rs
@@ -1,3 +1,5 @@
+use std::ffi::CString;
+
 use strum::{EnumProperty, IntoEnumIterator};
 use strum_macros::{AsRefStr, Display, EnumIter, EnumProperty, EnumString};

@@ -72,10 +74,8 @@ impl Context {
                let rel_path = self.sql.get_config(self, key);
                rel_path.map(|p| {
                    let v = unsafe {
-                        let n = to_cstring(p);
-                        let res = dc_get_abs_path(self, n);
-                        free(n as *mut libc::c_void);
-                        res
+                        let n = CString::yolo(p);
+                        dc_get_abs_path(self, n.as_ptr())
                    };
                    let r = to_string(v);
                    unsafe { free(v as *mut _) };
--- a/src/context.rs
+++ b/src/context.rs
@@ -483,7 +483,7 @@ pub unsafe fn dc_get_info(context: &Context) -> *mut libc::c_char {
        fingerprint_str,
    );

-    to_cstring(res)
+    res.strdup()
 }

 pub unsafe fn dc_get_version_str() -> *mut libc::c_char {
--- a/src/dc_array.rs
+++ b/src/dc_array.rs
@@ -271,7 +271,7 @@ pub unsafe fn dc_array_get_marker(array: *const dc_array_t, index: size_t) -> *m

    if let dc_array_t::Locations(v) = &*array {
        if let Some(s) = &v[index].marker {
-            to_cstring(s)
+            s.strdup()
        } else {
            std::ptr::null_mut()
        }
@@ -375,7 +375,7 @@ pub unsafe fn dc_array_get_string(
                    res + sep + &n.to_string()
                }
            });
-        to_cstring(res)
+        res.strdup()
    } else {
        panic!("Attempt to get string from array of other type");
    }
--- a/src/dc_chat.rs
+++ b/src/dc_chat.rs
@@ -137,14 +137,8 @@ pub fn dc_chat_load_from_db(chat: *mut Chat, chat_id: u32) -> bool {

            c.id = row.get(0)?;
            c.type_0 = row.get(1)?;
-            c.name = {
-                let raw: String = row.get(2)?;
-                unsafe { to_cstring(raw) }
-            };
-            c.grpid = {
-                let raw: String = row.get(3)?;
-                unsafe { to_cstring(raw) }
-            };
+            c.name = unsafe { row.get::<_, String>(2)?.strdup() };
+            c.grpid = unsafe { row.get::<_, String>(3)?.strdup() };

            c.param = row.get::<_, String>(4)?.parse().unwrap_or_default();
            c.archived = row.get(5)?;
@@ -172,24 +166,27 @@ pub fn dc_chat_load_from_db(chat: *mut Chat, chat_id: u32) -> bool {
            match c.id {
                1 => unsafe {
                    free((*chat).name as *mut libc::c_void);
-                    (*chat).name = to_cstring((*chat).context.stock_str(StockMessage::DeadDrop));
+                    (*chat).name = (*chat).context.stock_str(StockMessage::DeadDrop).strdup();
                },
                6 => unsafe {
                    free((*chat).name as *mut libc::c_void);
                    let tempname = (*chat).context.stock_str(StockMessage::ArchivedChats);
                    let cnt = dc_get_archived_cnt((*chat).context);
-                    (*chat).name = to_cstring(format!("{} ({})", tempname, cnt));
+                    (*chat).name = format!("{} ({})", tempname, cnt).strdup();
                },
                5 => unsafe {
                    free((*chat).name as *mut libc::c_void);
-                    (*chat).name = to_cstring((*chat).context.stock_str(StockMessage::StarredMsgs));
+                    (*chat).name = (*chat)
+                        .context
+                        .stock_str(StockMessage::StarredMsgs)
+                        .strdup();
                },
                _ => {
                    if unsafe { &(*chat).param }.exists(Param::Selftalk) {
                        unsafe {
                            free((*chat).name as *mut libc::c_void);
                            (*chat).name =
-                                to_cstring((*chat).context.stock_str(StockMessage::SelfMsg));
+                                (*chat).context.stock_str(StockMessage::SelfMsg).strdup();
                        }
                    }
                }
@@ -398,7 +395,7 @@ unsafe fn prepare_msg_common<'a>(
        let mut pathNfilename = (*msg)
            .param
            .get(Param::File)
-            .map(|s| to_cstring(s))
+            .map(|s| s.strdup())
            .unwrap_or_else(|| std::ptr::null_mut());
        if pathNfilename.is_null() {
            error!(
@@ -516,16 +513,15 @@ unsafe fn prepare_msg_raw(
        if from.is_none() {
            error!(context, 0, "Cannot send message, not configured.",);
        } else {
-            let from_c = to_cstring(from.unwrap());
+            let from_c = CString::yolo(from.unwrap());
            new_rfc724_mid = dc_create_outgoing_rfc724_mid(
                if (*chat).type_0 == 120 || (*chat).type_0 == 130 {
                    (*chat).grpid
                } else {
                    0 as *mut libc::c_char
                },
-                from_c,
+                from_c.as_ptr(),
            );
-            free(from_c as *mut _);

            if (*chat).type_0 == DC_CHAT_TYPE_SINGLE {
                if let Some(id) = context.sql.query_row_col(
@@ -789,9 +785,9 @@ unsafe fn get_parent_mime_headers(
                 FROM msgs WHERE chat_id=? AND from_id!=?);",
                params![(*chat).id as i32, 1],
                |row| {
-                    *parent_rfc724_mid = to_cstring(row.get::<_, String>(0)?);
-                    *parent_in_reply_to = to_cstring(row.get::<_, String>(1)?);
-                    *parent_references = to_cstring(row.get::<_, String>(2)?);
+                    *parent_rfc724_mid = row.get::<_, String>(0)?.strdup();
+                    *parent_in_reply_to = row.get::<_, String>(1)?.strdup();
+                    *parent_references = row.get::<_, String>(2)?.strdup();
                    Ok(())
                },
            )
@@ -807,9 +803,9 @@ unsafe fn get_parent_mime_headers(
                     FROM msgs WHERE chat_id=? AND from_id==?);",
                    params![(*chat).id as i32, 1],
                    |row| {
-                        *parent_rfc724_mid = to_cstring(row.get::<_, String>(0)?);
-                        *parent_in_reply_to = to_cstring(row.get::<_, String>(1)?);
-                        *parent_references = to_cstring(row.get::<_, String>(2)?);
+                        *parent_rfc724_mid = row.get::<_, String>(0)?.strdup();
+                        *parent_in_reply_to = row.get::<_, String>(1)?.strdup();
+                        *parent_references = row.get::<_, String>(2)?.strdup();
                        Ok(())
                    },
                )
@@ -1012,7 +1008,7 @@ unsafe fn set_draft_raw(context: &Context, chat_id: uint32_t, msg: *mut dc_msg_t
            let mut pathNfilename = (*msg)
                .param
                .get(Param::File)
-                .map(|s| to_cstring(s))
+                .map(|s| s.strdup())
                .unwrap_or_else(|| std::ptr::null_mut());
            if pathNfilename.is_null() {
                OK_TO_CONTINUE = false;
@@ -1620,12 +1616,14 @@ pub unsafe fn dc_add_contact_to_chat_ex(
                    if OK_TO_CONTINUE {
                        if (*chat).param.get_int(Param::Unpromoted).unwrap_or_default() == 0 {
                            (*msg).type_0 = Viewtype::Text;
-                            (*msg).text = to_cstring(context.stock_system_msg(
-                                StockMessage::MsgAddMember,
-                                as_str((*contact).addr),
-                                "",
-                                DC_CONTACT_ID_SELF as uint32_t,
-                            ));
+                            (*msg).text = context
+                                .stock_system_msg(
+                                    StockMessage::MsgAddMember,
+                                    as_str((*contact).addr),
+                                    "",
+                                    DC_CONTACT_ID_SELF as uint32_t,
+                                )
+                                .strdup();
                            (*msg).param.set_int(Param::Cmd, 4);
                            if !(*contact).addr.is_null() {
                                (*msg).param.set(Param::Arg, as_str((*contact).addr));
@@ -1733,19 +1731,23 @@ pub unsafe fn dc_remove_contact_from_chat(
                        (*msg).type_0 = Viewtype::Text;
                        if (*contact).id == 1 as libc::c_uint {
                            dc_set_group_explicitly_left(context, (*chat).grpid);
-                            (*msg).text = to_cstring(context.stock_system_msg(
-                                StockMessage::MsgGroupLeft,
-                                "",
-                                "",
-                                DC_CONTACT_ID_SELF as u32,
-                            ));
+                            (*msg).text = context
+                                .stock_system_msg(
+                                    StockMessage::MsgGroupLeft,
+                                    "",
+                                    "",
+                                    DC_CONTACT_ID_SELF as u32,
+                                )
+                                .strdup();
                        } else {
-                            (*msg).text = to_cstring(context.stock_system_msg(
-                                StockMessage::MsgDelMember,
-                                as_str((*contact).addr),
-                                "",
-                                DC_CONTACT_ID_SELF as u32,
-                            ));
+                            (*msg).text = context
+                                .stock_system_msg(
+                                    StockMessage::MsgDelMember,
+                                    as_str((*contact).addr),
+                                    "",
+                                    DC_CONTACT_ID_SELF as u32,
+                                )
+                                .strdup();
                        }
                        (*msg).param.set_int(Param::Cmd, 5);
                        if !(*contact).addr.is_null() {
@@ -1846,12 +1848,14 @@ pub unsafe fn dc_set_chat_name(
                {
                    if (*chat).param.get_int(Param::Unpromoted).unwrap_or_default() == 0 {
                        (*msg).type_0 = Viewtype::Text;
-                        (*msg).text = to_cstring(context.stock_system_msg(
-                            StockMessage::MsgGrpName,
-                            as_str((*chat).name),
-                            as_str(new_name),
-                            DC_CONTACT_ID_SELF as u32,
-                        ));
+                        (*msg).text = context
+                            .stock_system_msg(
+                                StockMessage::MsgGrpName,
+                                as_str((*chat).name),
+                                as_str(new_name),
+                                DC_CONTACT_ID_SELF as u32,
+                            )
+                            .strdup();
                        (*msg).param.set_int(Param::Cmd, 2);
                        if !(*chat).name.is_null() {
                            (*msg).param.set(Param::Arg, as_str((*chat).name));
@@ -1918,16 +1922,18 @@ pub unsafe fn dc_set_chat_profile_image(
                            (*msg).param.set_int(Param::Cmd, 3);
                            (*msg).param.set(Param::Arg, as_str(new_image_rel));
                            (*msg).type_0 = Viewtype::Text;
-                            (*msg).text = to_cstring(context.stock_system_msg(
-                                if !new_image_rel.is_null() {
-                                    StockMessage::MsgGrpImgChanged
-                                } else {
-                                    StockMessage::MsgGrpImgDeleted
-                                },
-                                "",
-                                "",
-                                DC_CONTACT_ID_SELF as uint32_t,
-                            ));
+                            (*msg).text = context
+                                .stock_system_msg(
+                                    if !new_image_rel.is_null() {
+                                        StockMessage::MsgGrpImgChanged
+                                    } else {
+                                        StockMessage::MsgGrpImgDeleted
+                                    },
+                                    "",
+                                    "",
+                                    DC_CONTACT_ID_SELF as uint32_t,
+                                )
+                                .strdup();
                            (*msg).id = dc_send_msg(context, chat_id, msg);
                            context.call_cb(
                                Event::MSGS_CHANGED,
@@ -2094,7 +2100,10 @@ pub unsafe fn dc_chat_get_subtitle(chat: *const Chat) -> *mut libc::c_char {

    let mut ret: *mut libc::c_char = std::ptr::null_mut();
    if (*chat).type_0 == 100 && (*chat).param.exists(Param::Selftalk) {
-        ret = to_cstring((*chat).context.stock_str(StockMessage::SelfTalkSubTitle));
+        ret = (*chat)
+            .context
+            .stock_str(StockMessage::SelfTalkSubTitle)
+            .strdup();
    } else if (*chat).type_0 == 100 {
        let ret_raw: String = (*chat)
            .context
@@ -2108,17 +2117,16 @@ pub unsafe fn dc_chat_get_subtitle(chat: *const Chat) -> *mut libc::c_char {
                0,
            )
            .unwrap_or_else(|| "Err".into());
-        ret = to_cstring(ret_raw);
+        ret = ret_raw.strdup();
    } else if (*chat).type_0 == 120 || (*chat).type_0 == 130 {
        if (*chat).id == 1 {
-            ret = to_cstring((*chat).context.stock_str(StockMessage::DeadDrop));
+            ret = (*chat).context.stock_str(StockMessage::DeadDrop).strdup();
        } else {
            let cnt = dc_get_chat_contact_cnt((*chat).context, (*chat).id);
-            ret = to_cstring(
-                (*chat)
-                    .context
-                    .stock_string_repl_int(StockMessage::Member, cnt),
-            );
+            ret = (*chat)
+                .context
+                .stock_string_repl_int(StockMessage::Member, cnt)
+                .strdup();
        }
    }
    return if !ret.is_null() {
@@ -2146,7 +2154,11 @@ pub unsafe fn dc_chat_get_profile_image(chat: *const Chat) -> *mut libc::c_char
    let mut contacts: *mut dc_array_t = 0 as *mut dc_array_t;
    let mut contact: *mut dc_contact_t = 0 as *mut dc_contact_t;
    if !(chat.is_null() || (*chat).magic != 0xc4a7c4a7u32) {
-        image_rel = to_cstring((*chat).param.get(Param::ProfileImage).unwrap_or_default());
+        image_rel = (*chat)
+            .param
+            .get(Param::ProfileImage)
+            .unwrap_or_default()
+            .strdup();
        if !image_rel.is_null() && 0 != *image_rel.offset(0isize) as libc::c_int {
            image_abs = dc_get_abs_path((*chat).context, image_rel)
        } else if (*chat).type_0 == 100i32 {
--- a/src/dc_configure.rs
+++ b/src/dc_configure.rs
@@ -1102,14 +1102,14 @@ unsafe fn moz_autoconfigure(
        tag_config: 0,
    };

-    let url_c = to_cstring(url);
+    let url_c = url.strdup();
    let xml_raw = read_autoconf_file(context, url_c);
    free(url_c as *mut libc::c_void);
    if xml_raw.is_null() {
        return None;
    }

-    moz_ac.in_emaillocalpart = to_cstring(&param_in.addr);
+    moz_ac.in_emaillocalpart = param_in.addr.strdup();
    let p = strchr(moz_ac.in_emaillocalpart, '@' as i32);

    if p.is_null() {
@@ -1166,7 +1166,7 @@ unsafe fn moz_autoconfigure_text_cb(
    let mut moz_ac: *mut moz_autoconfigure_t = userdata as *mut moz_autoconfigure_t;
    let mut val: *mut libc::c_char = dc_strdup(text);
    dc_trim(val);
-    let addr = to_cstring(&(*moz_ac).in_0.addr);
+    let addr = (*moz_ac).in_0.addr.strdup();
    dc_str_replace(
        &mut val,
        b"%EMAILADDRESS%\x00" as *const u8 as *const libc::c_char,
@@ -1306,7 +1306,7 @@ fn read_autoconf_file(context: &Context, url: *const libc::c_char) -> *mut libc:
        .send()
        .and_then(|mut res| res.text())
    {
-        Ok(res) => unsafe { to_cstring(res) },
+        Ok(res) => unsafe { res.strdup() },
        Err(_err) => {
            info!(context, 0, "Can\'t read file.",);

@@ -1322,7 +1322,7 @@ unsafe fn outlk_autodiscover(
 ) -> Option<dc_loginparam_t> {
    let current_block: u64;
    let mut xml_raw: *mut libc::c_char = 0 as *mut libc::c_char;
-    let mut url = to_cstring(url__);
+    let mut url = url__.strdup();
    let mut outlk_ad = outlk_autodiscover_t {
        in_0: param_in,
        out: dc_loginparam_new(),
--- a/src/dc_contact.rs
+++ b/src/dc_contact.rs
@@ -278,14 +278,13 @@ pub unsafe fn dc_contact_load_from_db(

    if contact_id == 1 as libc::c_uint {
        (*contact).id = contact_id;
-        (*contact).name = to_cstring((*contact).context.stock_str(StockMessage::SelfMsg));
-        (*contact).addr = to_cstring(
-            (*contact)
-                .context
-                .sql
-                .get_config((*contact).context, "configured_addr")
-                .unwrap_or_default(),
-        );
+        (*contact).name = (*contact).context.stock_str(StockMessage::SelfMsg).strdup();
+        (*contact).addr = (*contact)
+            .context
+            .sql
+            .get_config((*contact).context, "configured_addr")
+            .unwrap_or_default()
+            .strdup();
        true
    } else {
        sql.query_row(
@@ -293,11 +292,11 @@ pub unsafe fn dc_contact_load_from_db(
            params![contact_id as i32],
            |row| {
                (*contact).id = contact_id;
-                (*contact).name = to_cstring(row.get::<_, String>(0)?);
-                (*contact).addr = to_cstring(row.get::<_, String>(1)?);
+                (*contact).name = row.get::<_, String>(0)?.strdup();
+                (*contact).addr = row.get::<_, String>(1)?.strdup();
                (*contact).origin = row.get(2)?;
                (*contact).blocked = row.get::<_, Option<i32>>(3)?.unwrap_or_default();
-                (*contact).authname = to_cstring(row.get::<_, String>(4)?);
+                (*contact).authname = row.get::<_, String>(4)?.strdup();
                Ok(())
            }
        ).is_ok()
@@ -726,7 +725,7 @@ pub unsafe fn dc_get_contact_encrinfo(
    free(fingerprint_other_verified as *mut libc::c_void);
    free(fingerprint_other_unverified as *mut libc::c_void);

-    to_cstring(ret)
+    ret.strdup()
 }

 unsafe fn cat_fingerprint(
@@ -901,7 +900,7 @@ pub fn dc_contact_get_profile_image(contact: *const dc_contact_t) -> *mut libc::
    if unsafe { (*contact).id } == 1 {
        let context = unsafe { (*contact) }.context;
        if let Some(avatar) = context.get_config(config::Config::Selfavatar) {
-            image_abs = unsafe { to_cstring(avatar) };
+            image_abs = unsafe { avatar.strdup() };
        }
    }
    // TODO: else get image_abs from contact param
--- a/src/dc_dehtml.rs
+++ b/src/dc_dehtml.rs
@@ -53,7 +53,7 @@ pub unsafe fn dc_dehtml(buf_terminated: *mut libc::c_char) -> *mut libc::c_char
    dc_saxparser_parse(&mut saxparser, buf_terminated);
    free(dehtml.last_href as *mut libc::c_void);

-    to_cstring(dehtml.strbuilder)
+    dehtml.strbuilder.strdup()
 }

 unsafe fn dehtml_text_cb(
--- a/src/dc_e2ee.rs
+++ b/src/dc_e2ee.rs
@@ -177,16 +177,12 @@ pub unsafe fn dc_e2ee_encrypt(
                                    let p = peerstates[i as usize]
                                        .render_gossip_header(min_verified as usize);

-                                    if p.is_some() {
-                                        let header = to_cstring(p.unwrap());
+                                    if let Some(header) = p {
                                        mailimf_fields_add(
                                            imffields_encrypted,
                                            mailimf_field_new_custom(
-                                                strdup(
-                                                    b"Autocrypt-Gossip\x00" as *const u8
-                                                        as *const libc::c_char,
-                                                ),
-                                                header,
+                                                "Autocrypt-Gossip".strdup(),
+                                                header.strdup(),
                                            ),
                                        );
                                    }
@@ -296,7 +292,7 @@ pub unsafe fn dc_e2ee_encrypt(
                                sign_key.as_ref(),
                            ) {
                                let ctext_bytes = ctext_v.len();
-                                let ctext = to_cstring(ctext_v);
+                                let ctext = ctext_v.strdup();
                                (*helper).cdata_to_free = ctext as *mut _;

                                /* create MIME-structure that will contain the encrypted text */
@@ -354,13 +350,11 @@ pub unsafe fn dc_e2ee_encrypt(
                        14181132614457621749 => {}
                        _ => {
                            let aheader = Aheader::new(addr, public_key, prefer_encrypt);
-                            let rendered = to_cstring(aheader.to_string());
-
                            mailimf_fields_add(
                                imffields_unprotected,
                                mailimf_field_new_custom(
-                                    strdup(b"Autocrypt\x00" as *const u8 as *const libc::c_char),
-                                    rendered,
+                                    "Autocrypt".strdup(),
+                                    aheader.to_string().strdup(),
                                ),
                            );
                        }
--- a/src/dc_imex.rs
+++ b/src/dc_imex.rs
@@ -515,7 +515,7 @@ pub unsafe fn dc_normalize_setup_code(
        p1 = p1.offset(1);
    }

-    to_cstring(out)
+    out.strdup()
 }

 #[allow(non_snake_case)]
@@ -524,16 +524,14 @@ pub unsafe fn dc_job_do_DC_JOB_IMEX_IMAP(context: &Context, job: *mut dc_job_t)
    let mut success: libc::c_int = 0;
    let mut ongoing_allocated_here: libc::c_int = 0;
    let what: libc::c_int;
-    let mut param1 = 0 as *mut libc::c_char;
-    let mut param2 = 0 as *mut libc::c_char;

    if !(0 == dc_alloc_ongoing(context)) {
        ongoing_allocated_here = 1;
        what = (*job).param.get_int(Param::Cmd).unwrap_or_default();
-        param1 = to_cstring((*job).param.get(Param::Arg).unwrap_or_default());
-        param2 = to_cstring((*job).param.get(Param::Arg2).unwrap_or_default());
+        let param1 = CString::yolo((*job).param.get(Param::Arg).unwrap_or_default());
+        let _param2 = CString::yolo((*job).param.get(Param::Arg2).unwrap_or_default());

-        if strlen(param1) == 0 {
+        if strlen(param1.as_ptr()) == 0 {
            error!(context, 0, "No Import/export dir/file given.",);
        } else {
            info!(context, 0, "Import/export process started.",);
@@ -551,7 +549,7 @@ pub unsafe fn dc_job_do_DC_JOB_IMEX_IMAP(context: &Context, job: *mut dc_job_t)
                        );
                        current_block = 3568988166330621280;
                    } else {
-                        dc_create_folder(context, param1);
+                        dc_create_folder(context, param1.as_ptr());
                        current_block = 4495394744059808450;
                    }
                } else {
@@ -564,28 +562,28 @@ pub unsafe fn dc_job_do_DC_JOB_IMEX_IMAP(context: &Context, job: *mut dc_job_t)
                            current_block = 10991094515395304355;
                            match current_block {
                                2973387206439775448 => {
-                                    if 0 == import_backup(context, param1) {
+                                    if 0 == import_backup(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                11250025114629486028 => {
-                                    if 0 == import_self_keys(context, param1) {
+                                    if 0 == import_self_keys(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                12669919903773909120 => {
-                                    if 0 == export_backup(context, param1) {
+                                    if 0 == export_backup(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                _ => {
-                                    if 0 == export_self_keys(context, param1) {
+                                    if 0 == export_self_keys(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
@@ -604,28 +602,28 @@ pub unsafe fn dc_job_do_DC_JOB_IMEX_IMAP(context: &Context, job: *mut dc_job_t)
                            current_block = 11250025114629486028;
                            match current_block {
                                2973387206439775448 => {
-                                    if 0 == import_backup(context, param1) {
+                                    if 0 == import_backup(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                11250025114629486028 => {
-                                    if 0 == import_self_keys(context, param1) {
+                                    if 0 == import_self_keys(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                12669919903773909120 => {
-                                    if 0 == export_backup(context, param1) {
+                                    if 0 == export_backup(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                _ => {
-                                    if 0 == export_self_keys(context, param1) {
+                                    if 0 == export_self_keys(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
@@ -644,28 +642,28 @@ pub unsafe fn dc_job_do_DC_JOB_IMEX_IMAP(context: &Context, job: *mut dc_job_t)
                            current_block = 12669919903773909120;
                            match current_block {
                                2973387206439775448 => {
-                                    if 0 == import_backup(context, param1) {
+                                    if 0 == import_backup(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                11250025114629486028 => {
-                                    if 0 == import_self_keys(context, param1) {
+                                    if 0 == import_self_keys(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                12669919903773909120 => {
-                                    if 0 == export_backup(context, param1) {
+                                    if 0 == export_backup(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                _ => {
-                                    if 0 == export_self_keys(context, param1) {
+                                    if 0 == export_self_keys(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
@@ -684,28 +682,28 @@ pub unsafe fn dc_job_do_DC_JOB_IMEX_IMAP(context: &Context, job: *mut dc_job_t)
                            current_block = 2973387206439775448;
                            match current_block {
                                2973387206439775448 => {
-                                    if 0 == import_backup(context, param1) {
+                                    if 0 == import_backup(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                11250025114629486028 => {
-                                    if 0 == import_self_keys(context, param1) {
+                                    if 0 == import_self_keys(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                12669919903773909120 => {
-                                    if 0 == export_backup(context, param1) {
+                                    if 0 == export_backup(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
                                    }
                                }
                                _ => {
-                                    if 0 == export_self_keys(context, param1) {
+                                    if 0 == export_self_keys(context, param1.as_ptr()) {
                                        current_block = 3568988166330621280;
                                    } else {
                                        current_block = 1118134448028020070;
@@ -727,8 +725,6 @@ pub unsafe fn dc_job_do_DC_JOB_IMEX_IMAP(context: &Context, job: *mut dc_job_t)
        }
    }

-    free(param1 as *mut libc::c_void);
-    free(param2 as *mut libc::c_void);
    if 0 != ongoing_allocated_here {
        dc_free_ongoing(context);
    }
@@ -875,9 +871,8 @@ unsafe fn export_backup(context: &Context, dir: *const libc::c_char) -> libc::c_
    let res = chrono::NaiveDateTime::from_timestamp(now as i64, 0)
        .format("delta-chat-%Y-%m-%d.bak")
        .to_string();
-    let buffer = to_cstring(res);
-    let dest_pathNfilename = dc_get_fine_pathNfilename(context, dir, buffer);
-    free(buffer as *mut _);
+    let buffer = CString::yolo(res);
+    let dest_pathNfilename = dc_get_fine_pathNfilename(context, dir, buffer.as_ptr());
    if dest_pathNfilename.is_null() {
        error!(context, 0, "Cannot get backup file name.",);

@@ -1076,7 +1071,6 @@ unsafe fn import_self_keys(context: &Context, dir_name: *const libc::c_char) ->
    let mut imported_cnt: libc::c_int = 0;
    let mut suffix: *mut libc::c_char = 0 as *mut libc::c_char;
    let mut path_plus_name: *mut libc::c_char = 0 as *mut libc::c_char;
-    let mut name_c: *mut libc::c_char = 0 as *mut libc::c_char;
    let mut set_default: libc::c_int;
    let mut buf: *mut libc::c_char = 0 as *mut libc::c_char;
    let mut buf_bytes: size_t = 0 as size_t;
@@ -1104,9 +1098,8 @@ unsafe fn import_self_keys(context: &Context, dir_name: *const libc::c_char) ->
                let entry = entry.unwrap();
                free(suffix as *mut libc::c_void);
                let name_f = entry.file_name();
-                free(name_c as *mut libc::c_void);
-                name_c = to_cstring(name_f.to_string_lossy());
-                suffix = dc_get_filesuffix_lc(name_c);
+                let name_c = name_f.to_c_string().unwrap();
+                suffix = dc_get_filesuffix_lc(name_c.as_ptr());
                if suffix.is_null()
                    || strcmp(suffix, b"asc\x00" as *const u8 as *const libc::c_char) != 0
                {
@@ -1116,7 +1109,7 @@ unsafe fn import_self_keys(context: &Context, dir_name: *const libc::c_char) ->
                path_plus_name = dc_mprintf(
                    b"%s/%s\x00" as *const u8 as *const libc::c_char,
                    dir_name,
-                    name_c,
+                    name_c.as_ptr(),
                );
                info!(context, 0, "Checking: {}", as_str(path_plus_name));
                free(buf as *mut libc::c_void);
@@ -1154,7 +1147,12 @@ unsafe fn import_self_keys(context: &Context, dir_name: *const libc::c_char) ->
                    }
                }
                set_default = 1;
-                if !strstr(name_c, b"legacy\x00" as *const u8 as *const libc::c_char).is_null() {
+                if !strstr(
+                    name_c.as_ptr(),
+                    b"legacy\x00" as *const u8 as *const libc::c_char,
+                )
+                .is_null()
+                {
                    info!(
                        context,
                        0,
@@ -1179,7 +1177,6 @@ unsafe fn import_self_keys(context: &Context, dir_name: *const libc::c_char) ->
        }
    }

-    free(name_c as *mut libc::c_void);
    free(suffix as *mut libc::c_void);
    free(path_plus_name as *mut libc::c_void);
    free(buf as *mut libc::c_void);
--- a/src/dc_job.rs
+++ b/src/dc_job.rs
@@ -314,7 +314,7 @@ unsafe fn dc_job_do_DC_JOB_SEND(context: &Context, job: &mut dc_job_t) {
    }
    match current_block {
        13109137661213826276 => {
-            filename = to_cstring(job.param.get(Param::File).unwrap_or_default());
+            filename = job.param.get(Param::File).unwrap_or_default().strdup();
            if strlen(filename) == 0 {
                warn!(context, 0, "Missing file name for job {}", job.job_id,);
            } else if !(0 == dc_read_file(context, filename, &mut buf, &mut buf_bytes)) {
@@ -1177,12 +1177,11 @@ pub unsafe fn dc_job_send_msg(context: &Context, msg_id: uint32_t) -> libc::c_in
    } else {
        // no redo, no IMAP. moreover, as the data does not exist, there is no need in calling dc_set_msg_failed()
        if msgtype_has_file((*mimefactory.msg).type_0) {
-            let pathNfilename = to_cstring(
-                (*mimefactory.msg)
-                    .param
-                    .get(Param::File)
-                    .unwrap_or_default(),
-            );
+            let pathNfilename = (*mimefactory.msg)
+                .param
+                .get(Param::File)
+                .unwrap_or_default()
+                .strdup();
            if strlen(pathNfilename) > 0 {
                if ((*mimefactory.msg).type_0 == Viewtype::Image
                    || (*mimefactory.msg).type_0 == Viewtype::Gif)
--- a/src/dc_location.rs
+++ b/src/dc_location.rs
@@ -100,12 +100,9 @@ pub unsafe fn dc_send_locations_to_chat(
        {
            if 0 != seconds && !is_sending_locations_before {
                msg = dc_msg_new(context, Viewtype::Text);
-                (*msg).text = to_cstring(context.stock_system_msg(
-                    StockMessage::MsgLocationEnabled,
-                    "",
-                    "",
-                    0,
-                ));
+                (*msg).text = context
+                    .stock_system_msg(StockMessage::MsgLocationEnabled, "", "", 0)
+                    .strdup();
                (*msg).param.set_int(Param::Cmd, 8);
                dc_send_msg(context, chat_id, msg);
            } else if 0 == seconds && is_sending_locations_before {
@@ -351,7 +348,7 @@ pub fn dc_get_location_kml(
    }

    if 0 != success {
-        unsafe { to_cstring(ret) }
+        unsafe { ret.strdup() }
    } else {
        std::ptr::null_mut()
    }
@@ -365,7 +362,7 @@ unsafe fn get_kml_timestamp(utc: i64) -> *mut libc::c_char {
    let res = chrono::NaiveDateTime::from_timestamp(utc, 0)
        .format("%Y-%m-%dT%H:%M:%SZ")
        .to_string();
-    to_cstring(res)
+    res.strdup()
 }

 pub unsafe fn dc_get_message_kml(
--- a/src/dc_lot.rs
+++ b/src/dc_lot.rs
@@ -134,14 +134,14 @@ pub unsafe fn dc_lot_fill(
        return;
    }
    if (*msg).state == 19i32 {
-        (*lot).text1 = to_cstring(context.stock_str(StockMessage::Draft));
+        (*lot).text1 = context.stock_str(StockMessage::Draft).strdup();
        (*lot).text1_meaning = 1i32
    } else if (*msg).from_id == 1i32 as libc::c_uint {
        if 0 != dc_msg_is_info(msg) || 0 != dc_chat_is_self_talk(chat) {
            (*lot).text1 = 0 as *mut libc::c_char;
            (*lot).text1_meaning = 0i32
        } else {
-            (*lot).text1 = to_cstring(context.stock_str(StockMessage::SelfMsg));
+            (*lot).text1 = context.stock_str(StockMessage::SelfMsg).strdup();
            (*lot).text1_meaning = 3i32
        }
    } else if chat.is_null() {
--- a/src/dc_mimefactory.rs
+++ b/src/dc_mimefactory.rs
@@ -158,13 +158,13 @@ pub unsafe fn dc_mimefactory_load_msg(
                    |rows| {
                        for row in rows {
                            let (authname, addr) = row?;
-                            let addr_c = to_cstring(addr);
+                            let addr_c = addr.strdup();
                            if clist_search_string_nocase((*factory).recipients_addr, addr_c) == 0 {
                                clist_insert_after(
                                    (*factory).recipients_names,
                                    (*(*factory).recipients_names).last,
                                    if !authname.is_empty() {
-                                        to_cstring(authname)
+                                        authname.strdup()
                                    } else {
                                        std::ptr::null_mut()
                                    } as *mut libc::c_void,
@@ -188,7 +188,7 @@ pub unsafe fn dc_mimefactory_load_msg(

            if command == 5 {
                let email_to_remove = (*(*factory).msg).param.get(Param::Arg).unwrap_or_default();
-                let email_to_remove_c = to_cstring(email_to_remove);
+                let email_to_remove_c = email_to_remove.strdup();

                let self_addr = context
                    .sql
@@ -234,8 +234,8 @@ pub unsafe fn dc_mimefactory_load_msg(
        );
        match row {
            Ok((in_reply_to, references)) => {
-                (*factory).in_reply_to = to_cstring(in_reply_to);
-                (*factory).references = to_cstring(references);
+                (*factory).in_reply_to = in_reply_to.strdup();
+                (*factory).references = references.strdup();
            }
            Err(err) => {
                error!(
@@ -259,27 +259,28 @@ pub unsafe fn dc_mimefactory_load_msg(

 unsafe fn load_from(mut factory: *mut dc_mimefactory_t) {
    let context = (*factory).context;
-    (*factory).from_addr = to_cstring(
-        context
-            .sql
-            .get_config(context, "configured_addr")
-            .unwrap_or_default(),
-    );
+    (*factory).from_addr = context
+        .sql
+        .get_config(context, "configured_addr")
+        .unwrap_or_default()
+        .strdup();

-    (*factory).from_displayname = to_cstring(
-        context
-            .sql
-            .get_config(context, "displayname")
-            .unwrap_or_default(),
-    );
-    (*factory).selfstatus = to_cstring(
-        context
-            .sql
-            .get_config(context, "selfstatus")
-            .unwrap_or_default(),
-    );
+    (*factory).from_displayname = context
+        .sql
+        .get_config(context, "displayname")
+        .unwrap_or_default()
+        .strdup();
+
+    (*factory).selfstatus = context
+        .sql
+        .get_config(context, "selfstatus")
+        .unwrap_or_default()
+        .strdup();
    if (*factory).selfstatus.is_null() {
-        (*factory).selfstatus = to_cstring((*factory).context.stock_str(StockMessage::StatusLine));
+        (*factory).selfstatus = (*factory)
+            .context
+            .stock_str(StockMessage::StatusLine)
+            .strdup();
    };
 }

@@ -573,8 +574,7 @@ pub unsafe fn dc_mimefactory_render(mut factory: *mut dc_mimefactory_t) -> libc:
                    ),
                );
                if command == 5 {
-                    let email_to_remove =
-                        to_cstring((*msg).param.get(Param::Arg).unwrap_or_default());
+                    let email_to_remove = (*msg).param.get(Param::Arg).unwrap_or_default().strdup();
                    if strlen(email_to_remove) > 0 {
                        mailimf_fields_add(
                            imf_fields,
@@ -589,7 +589,7 @@ pub unsafe fn dc_mimefactory_render(mut factory: *mut dc_mimefactory_t) -> libc:
                    }
                } else if command == 4 {
                    do_gossip = 1;
-                    let email_to_add = to_cstring((*msg).param.get(Param::Arg).unwrap_or_default());
+                    let email_to_add = (*msg).param.get(Param::Arg).unwrap_or_default().strdup();
                    if strlen(email_to_add) > 0 {
                        mailimf_fields_add(
                            imf_fields,
@@ -619,7 +619,7 @@ pub unsafe fn dc_mimefactory_render(mut factory: *mut dc_mimefactory_t) -> libc:
                        );
                    }
                } else if command == 2 {
-                    let value_to_add = to_cstring((*msg).param.get(Param::Arg).unwrap_or_default());
+                    let value_to_add = (*msg).param.get(Param::Arg).unwrap_or_default().strdup();
                    mailimf_fields_add(
                        imf_fields,
                        mailimf_field_new_custom(
@@ -661,11 +661,13 @@ pub unsafe fn dc_mimefactory_render(mut factory: *mut dc_mimefactory_t) -> libc:
                        strdup(b"v1\x00" as *const u8 as *const libc::c_char),
                    ),
                );
-                placeholdertext =
-                    to_cstring((*factory).context.stock_str(StockMessage::AcSetupMsgBody));
+                placeholdertext = (*factory)
+                    .context
+                    .stock_str(StockMessage::AcSetupMsgBody)
+                    .strdup();
            }
            if command == 7 {
-                let step = to_cstring((*msg).param.get(Param::Arg).unwrap_or_default());
+                let step = (*msg).param.get(Param::Arg).unwrap_or_default().strdup();
                if strlen(step) > 0 {
                    info!(
                        (*msg).context,
@@ -680,7 +682,7 @@ pub unsafe fn dc_mimefactory_render(mut factory: *mut dc_mimefactory_t) -> libc:
                            step,
                        ),
                    );
-                    let param2 = to_cstring((*msg).param.get(Param::Arg2).unwrap_or_default());
+                    let param2 = (*msg).param.get(Param::Arg2).unwrap_or_default().strdup();
                    if strlen(param2) > 0 {
                        mailimf_fields_add(
                            imf_fields,
@@ -708,7 +710,7 @@ pub unsafe fn dc_mimefactory_render(mut factory: *mut dc_mimefactory_t) -> libc:
                            ),
                        );
                    }
-                    let fingerprint = to_cstring((*msg).param.get(Param::Arg3).unwrap_or_default());
+                    let fingerprint = (*msg).param.get(Param::Arg3).unwrap_or_default().strdup();
                    if strlen(fingerprint) > 0 {
                        mailimf_fields_add(
                            imf_fields,
@@ -722,7 +724,7 @@ pub unsafe fn dc_mimefactory_render(mut factory: *mut dc_mimefactory_t) -> libc:
                        );
                    }
                    let grpid = match (*msg).param.get(Param::Arg4) {
-                        Some(id) => to_cstring(id),
+                        Some(id) => id.strdup(),
                        None => std::ptr::null_mut(),
                    };
                    if !grpid.is_null() {
@@ -958,25 +960,23 @@ pub unsafe fn dc_mimefactory_render(mut factory: *mut dc_mimefactory_t) -> libc:
                ) as *mut libc::c_void,
            );
            mailmime_add_part(message, multipart);
-            let p1: *mut libc::c_char;
-            let p2: *mut libc::c_char;
-            if 0 != (*(*factory).msg)
-                .param
-                .get_int(Param::GuranteeE2ee)
-                .unwrap_or_default()
+            let p1 = if 0
+                != (*(*factory).msg)
+                    .param
+                    .get_int(Param::GuranteeE2ee)
+                    .unwrap_or_default()
            {
-                p1 = to_cstring((*factory).context.stock_str(StockMessage::EncryptedMsg));
-            } else {
-                p1 = dc_msg_get_summarytext((*factory).msg, 32)
-            }
-            p2 = to_cstring(
                (*factory)
                    .context
-                    .stock_string_repl_str(StockMessage::ReadRcptMailBody, as_str(p1)),
-            );
-            message_text = dc_mprintf(b"%s\r\n\x00" as *const u8 as *const libc::c_char, p2);
-            free(p1 as *mut libc::c_void);
-            free(p2 as *mut libc::c_void);
+                    .stock_str(StockMessage::EncryptedMsg)
+                    .into_owned()
+            } else {
+                to_string(dc_msg_get_summarytext((*factory).msg, 32))
+            };
+            let p2 = (*factory)
+                .context
+                .stock_string_repl_str(StockMessage::ReadRcptMailBody, p1);
+            message_text = format!("{}\r\n", p2).strdup();
            let human_mime_part: *mut mailmime = build_body_text(message_text);
            mailmime_add_part(multipart, human_mime_part);
            message_text2 =
@@ -1102,7 +1102,7 @@ unsafe fn get_subject(
        b"\x00" as *const u8 as *const libc::c_char
    };
    if (*msg).param.get_int(Param::Cmd).unwrap_or_default() == 6 {
-        ret = to_cstring(context.stock_str(StockMessage::AcSetupMsgSubject))
+        ret = context.stock_str(StockMessage::AcSetupMsgSubject).strdup()
    } else if (*chat).type_0 == DC_CHAT_TYPE_GROUP as libc::c_int
        || (*chat).type_0 == DC_CHAT_TYPE_VERIFIED_GROUP as libc::c_int
    {
@@ -1165,12 +1165,12 @@ unsafe fn build_body_file(
    let pathNfilename = (*msg)
        .param
        .get(Param::File)
-        .map(|s| to_cstring(s))
+        .map(|s| s.strdup())
        .unwrap_or_else(|| std::ptr::null_mut());
    let mut mimetype = (*msg)
        .param
        .get(Param::MimeType)
-        .map(|s| to_cstring(s))
+        .map(|s| s.strdup())
        .unwrap_or_else(|| std::ptr::null_mut());

    let suffix = dc_get_filesuffix_lc(pathNfilename);
@@ -1189,7 +1189,7 @@ unsafe fn build_body_file(
            let res = ts
                .format(&format!("voice-message_%Y-%m-%d_%H-%M-%S.{}", suffix))
                .to_string();
-            filename_to_send = to_cstring(res);
+            filename_to_send = res.strdup();
        } else if (*msg).type_0 == Viewtype::Audio {
            filename_to_send = dc_get_filename(pathNfilename)
        } else if (*msg).type_0 == Viewtype::Image || (*msg).type_0 == Viewtype::Gif {
@@ -1329,7 +1329,7 @@ unsafe fn build_body_file(
 #[allow(non_snake_case)]
 unsafe fn is_file_size_okay(msg: *const dc_msg_t) -> bool {
    let mut file_size_okay = true;
-    let pathNfilename = to_cstring((*msg).param.get(Param::File).unwrap_or_default());
+    let pathNfilename = (*msg).param.get(Param::File).unwrap_or_default().strdup();
    let bytes = dc_get_filebytes((*msg).context, pathNfilename);

    if bytes > (49 * 1024 * 1024 / 4 * 3) {
--- a/src/dc_mimeparser.rs
+++ b/src/dc_mimeparser.rs
@@ -1312,9 +1312,8 @@ unsafe fn dc_mimeparser_add_single_part_if_known(
                        }
                        if !filename_parts.is_empty() {
                            free(desired_filename as *mut libc::c_void);
-                            let parts_c = to_cstring(filename_parts);
-                            desired_filename = dc_decode_ext_header(parts_c);
-                            free(parts_c as *mut _);
+                            let parts_c = CString::yolo(filename_parts);
+                            desired_filename = dc_decode_ext_header(parts_c.as_ptr());
                        }
                        if desired_filename.is_null() {
                            let param = mailmime_find_ct_parameter(
--- a/src/dc_msg.rs
+++ b/src/dc_msg.rs
@@ -65,7 +65,7 @@ pub unsafe fn dc_get_msg_info(context: &Context, msg_id: u32) -> *mut libc::c_ch
        ret += &format!("Cannot load message #{}.", msg_id as usize);
        dc_msg_unref(msg);
        dc_contact_unref(contact_from);
-        return to_cstring(ret);
+        return ret.strdup();
    }
    let rawtxt = rawtxt.unwrap();
    let rawtxt = dc_truncate_str(rawtxt.trim(), 100000);
@@ -92,7 +92,7 @@ pub unsafe fn dc_get_msg_info(context: &Context, msg_id: u32) -> *mut libc::c_ch
        // device-internal message, no further details needed
        dc_msg_unref(msg);
        dc_contact_unref(contact_from);
-        return to_cstring(ret);
+        return ret.strdup();
    }

    context
@@ -210,7 +210,7 @@ pub unsafe fn dc_get_msg_info(context: &Context, msg_id: u32) -> *mut libc::c_ch

    dc_msg_unref(msg);
    dc_contact_unref(contact_from);
-    to_cstring(ret)
+    ret.strdup()
 }

 pub unsafe fn dc_msg_new_untyped<'a>(context: &'a Context) -> *mut dc_msg_t<'a> {
@@ -288,18 +288,17 @@ pub unsafe fn dc_msg_get_filemime(msg: *const dc_msg_t) -> *mut libc::c_char {
    if !(msg.is_null() || (*msg).magic != 0x11561156i32 as libc::c_uint) {
        match (*msg).param.get(Param::MimeType) {
            Some(m) => {
-                ret = to_cstring(m);
+                ret = m.strdup();
            }
            None => {
                if let Some(file) = (*msg).param.get(Param::File) {
-                    let file_c = to_cstring(file);
-                    dc_msg_guess_msgtype_from_suffix(file_c, 0 as *mut Viewtype, &mut ret);
+                    let file_c = CString::yolo(file);
+                    dc_msg_guess_msgtype_from_suffix(file_c.as_ptr(), 0 as *mut Viewtype, &mut ret);
                    if ret.is_null() {
                        ret = dc_strdup(
                            b"application/octet-stream\x00" as *const u8 as *const libc::c_char,
                        )
                    }
-                    free(file_c as *mut _);
                }
            }
        }
@@ -372,9 +371,8 @@ pub unsafe fn dc_msg_get_file(msg: *const dc_msg_t) -> *mut libc::c_char {

    if !(msg.is_null() || (*msg).magic != 0x11561156i32 as libc::c_uint) {
        if let Some(file_rel) = (*msg).param.get(Param::File) {
-            let file_rel_c = to_cstring(file_rel);
-            file_abs = dc_get_abs_path((*msg).context, file_rel_c);
-            free(file_rel_c as *mut _);
+            let file_rel_c = CString::yolo(file_rel);
+            file_abs = dc_get_abs_path((*msg).context, file_rel_c.as_ptr());
        }
    }
    if !file_abs.is_null() {
@@ -464,12 +462,12 @@ pub fn dc_msg_load_from_db<'a>(msg: *mut dc_msg_t<'a>, context: &'a Context, id:
                dc_msg_empty(msg);

                (*msg).id = row.get::<_, i32>(0)? as u32;
-                (*msg).rfc724_mid = to_cstring(row.get::<_, String>(1)?);
+                (*msg).rfc724_mid = row.get::<_, String>(1)?.strdup();
                (*msg).in_reply_to = match row.get::<_, Option<String>>(2)? {
-                    Some(s) => to_cstring(s),
+                    Some(s) => s.strdup(),
                    None => std::ptr::null_mut(),
                };
-                (*msg).server_folder = to_cstring(row.get::<_, String>(3)?);
+                (*msg).server_folder = row.get::<_, String>(3)?.strdup();
                (*msg).server_uid = row.get(4)?;
                (*msg).move_state = row.get(5)?;
                (*msg).chat_id = row.get(6)?;
@@ -481,7 +479,7 @@ pub fn dc_msg_load_from_db<'a>(msg: *mut dc_msg_t<'a>, context: &'a Context, id:
                (*msg).type_0 = row.get(12)?;
                (*msg).state = row.get(13)?;
                (*msg).is_dc_message = row.get(14)?;
-                (*msg).text = to_cstring(row.get::<_, String>(15).unwrap_or_default());
+                (*msg).text = row.get::<_, String>(15).unwrap_or_default().strdup();
                (*msg).param = row.get::<_, String>(16)?.parse().unwrap_or_default();
                (*msg).starred = row.get(17)?;
                (*msg).hidden = row.get(18)?;
@@ -507,10 +505,8 @@ pub unsafe fn dc_get_mime_headers(context: &Context, msg_id: uint32_t) -> *mut l
    );

    if let Some(headers) = headers {
-        let h = to_cstring(headers);
-        let res = dc_strdup_keep_null(h);
-        free(h as *mut _);
-        res
+        let h = CString::yolo(headers);
+        dc_strdup_keep_null(h.as_ptr())
    } else {
        std::ptr::null_mut()
    }
@@ -711,7 +707,7 @@ pub unsafe fn dc_msg_get_text(msg: *const dc_msg_t) -> *mut libc::c_char {
    }

    let res = dc_truncate_str(as_str((*msg).text), 30000);
-    to_cstring(res)
+    res.strdup()
 }

 #[allow(non_snake_case)]
@@ -720,9 +716,8 @@ pub unsafe fn dc_msg_get_filename(msg: *const dc_msg_t) -> *mut libc::c_char {

    if !(msg.is_null() || (*msg).magic != 0x11561156i32 as libc::c_uint) {
        if let Some(file) = (*msg).param.get(Param::File) {
-            let file_c = to_cstring(file);
-            ret = dc_get_filename(file_c);
-            free(file_c as *mut _);
+            let file_c = CString::yolo(file);
+            ret = dc_get_filename(file_c.as_ptr());
        }
    }
    if !ret.is_null() {
@@ -737,9 +732,8 @@ pub unsafe fn dc_msg_get_filebytes(msg: *const dc_msg_t) -> uint64_t {

    if !(msg.is_null() || (*msg).magic != 0x11561156i32 as libc::c_uint) {
        if let Some(file) = (*msg).param.get(Param::File) {
-            let file_c = to_cstring(file);
-            ret = dc_get_filebytes((*msg).context, file_c);
-            free(file_c as *mut _);
+            let file_c = CString::yolo(file);
+            ret = dc_get_filebytes((*msg).context, file_c.as_ptr());
        }
    }

@@ -858,16 +852,19 @@ pub unsafe fn dc_msg_get_summarytext_by_raw(
    let mut value: *mut libc::c_char = 0 as *mut libc::c_char;
    let mut append_text: libc::c_int = 1i32;
    match type_0 {
-        Viewtype::Image => prefix = to_cstring(context.stock_str(StockMessage::Image)),
-        Viewtype::Gif => prefix = to_cstring(context.stock_str(StockMessage::Gif)),
-        Viewtype::Video => prefix = to_cstring(context.stock_str(StockMessage::Video)),
-        Viewtype::Voice => prefix = to_cstring(context.stock_str(StockMessage::VoiceMessage)),
+        Viewtype::Image => prefix = context.stock_str(StockMessage::Image).strdup(),
+        Viewtype::Gif => prefix = context.stock_str(StockMessage::Gif).strdup(),
+        Viewtype::Video => prefix = context.stock_str(StockMessage::Video).strdup(),
+        Viewtype::Voice => prefix = context.stock_str(StockMessage::VoiceMessage).strdup(),
        Viewtype::Audio | Viewtype::File => {
            if param.get_int(Param::Cmd) == Some(6) {
-                prefix = to_cstring(context.stock_str(StockMessage::AcSetupMsgSubject));
+                prefix = context.stock_str(StockMessage::AcSetupMsgSubject).strdup();
                append_text = 0i32
            } else {
-                pathNfilename = to_cstring(param.get(Param::File).unwrap_or_else(|| "ErrFilename"));
+                pathNfilename = param
+                    .get(Param::File)
+                    .unwrap_or_else(|| "ErrFilename")
+                    .strdup();
                value = dc_get_filename(pathNfilename);
                let label = CString::new(
                    context
@@ -888,7 +885,7 @@ pub unsafe fn dc_msg_get_summarytext_by_raw(
        }
        _ => {
            if param.get_int(Param::Cmd) == Some(9) {
-                prefix = to_cstring(context.stock_str(StockMessage::Location));
+                prefix = context.stock_str(StockMessage::Location).strdup();
                append_text = 0;
            }
        }
@@ -1387,7 +1384,7 @@ pub fn dc_rfc724_mid_exists(
        &[as_str(rfc724_mid)],
        |row| {
            if !ret_server_folder.is_null() {
-                unsafe { *ret_server_folder = to_cstring(row.get::<_, String>(0)?) };
+                unsafe { *ret_server_folder = row.get::<_, String>(0)?.strdup() };
            }
            if !ret_server_uid.is_null() {
                unsafe { *ret_server_uid = row.get(1)? };
--- a/src/dc_qr.rs
+++ b/src/dc_qr.rs
@@ -59,34 +59,34 @@ pub unsafe fn dc_check_qr(context: &Context, qr: *const libc::c_char) -> *mut dc
                let param: Params = as_str(fragment).parse().expect("invalid params");
                addr = param
                    .get(Param::Forwarded)
-                    .map(|s| to_cstring(s))
+                    .map(|s| s.strdup())
                    .unwrap_or_else(|| std::ptr::null_mut());
                if !addr.is_null() {
                    if let Some(ref name_enc) = param.get(Param::SetLongitude) {
                        let name_r = percent_decode_str(name_enc)
                            .decode_utf8()
                            .expect("invalid name");
-                        name = to_cstring(name_r);
+                        name = name_r.strdup();
                        dc_normalize_name(name);
                    }
                    invitenumber = param
                        .get(Param::ProfileImage)
-                        .map(|s| to_cstring(s))
+                        .map(|s| s.strdup())
                        .unwrap_or_else(|| std::ptr::null_mut());
                    auth = param
                        .get(Param::Auth)
-                        .map(|s| to_cstring(s))
+                        .map(|s| s.strdup())
                        .unwrap_or_else(|| std::ptr::null_mut());
                    grpid = param
                        .get(Param::GroupId)
-                        .map(|s| to_cstring(s))
+                        .map(|s| s.strdup())
                        .unwrap_or_else(|| std::ptr::null_mut());
                    if !grpid.is_null() {
                        if let Some(grpname_enc) = param.get(Param::GroupName) {
                            let grpname_r = percent_decode_str(grpname_enc)
                                .decode_utf8()
                                .expect("invalid groupname");
-                            grpname = to_cstring(grpname_r);
+                            grpname = grpname_r.strdup();
                        }
                    }
                }
@@ -253,7 +253,7 @@ pub unsafe fn dc_check_qr(context: &Context, qr: *const libc::c_char) -> *mut dc
                                        if let Some(peerstate) = peerstate {
                                            (*qr_parsed).state = 210i32;
                                            let addr_ptr = if let Some(ref addr) = peerstate.addr {
-                                                to_cstring(addr)
+                                                addr.strdup()
                                            } else {
                                                std::ptr::null()
                                            };
--- a/src/dc_receive_imf.rs
+++ b/src/dc_receive_imf.rs
@@ -1210,7 +1210,7 @@ unsafe fn create_or_lookup_group(
                                        grpimage = (*part)
                                            .param
                                            .get(Param::File)
-                                            .map(|s| to_cstring(s))
+                                            .map(|s| s.strdup())
                                            .unwrap_or_else(|| std::ptr::null_mut());
                                        ok = 1
                                    }
@@ -1407,10 +1407,12 @@ unsafe fn create_or_lookup_adhoc_group(
                            {
                                grpname = dc_strdup(mime_parser.subject)
                            } else {
-                                grpname = to_cstring(context.stock_string_repl_int(
-                                    StockMessage::Member,
-                                    dc_array_get_cnt(member_ids) as libc::c_int,
-                                ));
+                                grpname = context
+                                    .stock_string_repl_int(
+                                        StockMessage::Member,
+                                        dc_array_get_cnt(member_ids) as libc::c_int,
+                                    )
+                                    .strdup();
                            }
                            chat_id =
                                create_group_record(context, grpid, grpname, create_blocked, 0);
@@ -1519,7 +1521,7 @@ fn hex_hash(s: impl AsRef<str>) -> *const libc::c_char {
    let bytes = s.as_ref().as_bytes();
    let result = Sha256::digest(bytes);
    let result_hex = hex::encode(&result[..8]);
-    unsafe { to_cstring(result_hex) as *const _ }
+    unsafe { result_hex.strdup() as *const _ }
 }

 #[allow(non_snake_case)]
@@ -1604,7 +1606,7 @@ unsafe fn check_verified_properties(
    let contact = dc_contact_new(context);

    let verify_fail = |reason: String| {
-        *failure_reason = to_cstring(format!("{}. See \"Info\" for details.", reason));
+        *failure_reason = format!("{}. See \"Info\" for details.", reason).strdup();
        warn!(context, 0, "{}", reason);
    };

@@ -1714,7 +1716,7 @@ unsafe fn set_better_msg<T: AsRef<str>>(mime_parser: &dc_mimeparser_t, better_ms
            carray_get(mime_parser.parts, 0 as libc::c_uint) as *mut dc_mimepart_t;
        if (*part).type_0 == 10 {
            free((*part).msg as *mut libc::c_void);
-            (*part).msg = to_cstring(msg);
+            (*part).msg = msg.strdup();
        }
    };
 }
--- a/src/dc_securejoin.rs
+++ b/src/dc_securejoin.rs
@@ -40,7 +40,7 @@ pub unsafe fn dc_get_securejoin_qr(
    let mut chat = 0 as *mut Chat;
    let mut group_name = 0 as *mut libc::c_char;
    let mut group_name_urlencoded = 0 as *mut libc::c_char;
-    let mut qr = None;
+    let mut qr: Option<String> = None;

    dc_ensure_secret_key_exists(context);
    invitenumber = dc_token_lookup(context, DC_TOKEN_INVITENUMBER, group_chat_id);
@@ -64,7 +64,7 @@ pub unsafe fn dc_get_securejoin_qr(
        free(group_name_urlencoded as *mut libc::c_void);

        if let Some(qr) = qr {
-            to_cstring(qr)
+            qr.strdup()
        } else {
            std::ptr::null_mut()
        }
--- a/src/dc_simplify.rs
+++ b/src/dc_simplify.rs
@@ -229,7 +229,7 @@ impl dc_simplify_t {
        }
        dc_free_splitted_lines(lines);

-        to_cstring(ret)
+        ret.strdup()
    }
 }

--- a/src/dc_strencode.rs
+++ b/src/dc_strencode.rs
@@ -1,4 +1,4 @@
-use std::ffi::CStr;
+use std::ffi::{CStr, CString};

 use charset::Charset;
 use mmime::mailmime_decode::*;
@@ -710,9 +710,8 @@ unsafe fn print_hex(target: *mut libc::c_char, cur: *const libc::c_char) {
    assert!(!cur.is_null());

    let bytes = std::slice::from_raw_parts(cur as *const _, strlen(cur));
-    let raw = to_cstring(format!("={}", &hex::encode_upper(bytes)[..2]));
-    libc::memcpy(target as *mut _, raw as *const _, 4);
-    free(raw as *mut libc::c_void);
+    let raw = CString::yolo(format!("={}", &hex::encode_upper(bytes)[..2]));
+    libc::memcpy(target as *mut _, raw.as_ptr() as *const _, 4);
 }

 #[cfg(test)]
--- a/src/dc_token.rs
+++ b/src/dc_token.rs
@@ -42,7 +42,7 @@ pub fn dc_token_lookup(
            params![namespc as i32, foreign_id as i32],
            0,
        )
-        .map(|s| unsafe { to_cstring(s) })
+        .map(|s| unsafe { s.strdup() })
        .unwrap_or_else(|| std::ptr::null_mut())
 }

--- a/src/dc_tools.rs
+++ b/src/dc_tools.rs
@@ -178,14 +178,13 @@ pub unsafe fn dc_trim(buf: *mut libc::c_char) {

 /* the result must be free()'d */
 pub unsafe fn dc_strlower(in_0: *const libc::c_char) -> *mut libc::c_char {
-    to_cstring(to_string(in_0).to_lowercase())
+    to_string(in_0).to_lowercase().strdup()
 }

 pub unsafe fn dc_strlower_in_place(in_0: *mut libc::c_char) {
-    let raw = to_cstring(to_string(in_0).to_lowercase());
-    assert_eq!(strlen(in_0), strlen(raw));
-    memcpy(in_0 as *mut _, raw as *const _, strlen(in_0));
-    free(raw as *mut _);
+    let raw = CString::yolo(to_string(in_0).to_lowercase());
+    assert_eq!(strlen(in_0), strlen(raw.as_ptr()));
+    memcpy(in_0 as *mut _, raw.as_ptr() as *const _, strlen(in_0));
 }

 pub unsafe fn dc_str_contains(
@@ -233,7 +232,7 @@ pub unsafe fn dc_binary_to_uc_hex(buf: *const uint8_t, bytes: size_t) -> *mut li

    let buf = std::slice::from_raw_parts(buf, bytes);
    let raw = hex::encode_upper(buf);
-    to_cstring(raw)
+    raw.strdup()
 }

 /* remove all \r characters from string */
@@ -527,7 +526,7 @@ pub unsafe fn dc_str_from_clist(
        }
    }

-    to_cstring(res)
+    res.strdup()
 }

 pub unsafe fn dc_str_to_clist(
@@ -1236,10 +1235,8 @@ pub unsafe fn dc_write_file(
 #[allow(non_snake_case)]
 pub fn dc_write_file_safe(context: &Context, pathNfilename: impl AsRef<str>, buf: &[u8]) -> bool {
    let pathNfilename_abs = unsafe {
-        let n = to_cstring(pathNfilename.as_ref());
-        let res = dc_get_abs_path(context, n);
-        free(n as *mut _);
-        res
+        let n = CString::yolo(pathNfilename.as_ref());
+        dc_get_abs_path(context, n.as_ptr())
    };
    if pathNfilename_abs.is_null() {
        return false;
@@ -1287,10 +1284,8 @@ pub unsafe fn dc_read_file(
 #[allow(non_snake_case)]
 pub fn dc_read_file_safe(context: &Context, pathNfilename: impl AsRef<str>) -> Option<Vec<u8>> {
    let pathNfilename_abs = unsafe {
-        let n = to_cstring(pathNfilename.as_ref());
-        let p = dc_get_abs_path(context, n);
-        free(n as *mut _);
-        p
+        let n = CString::yolo(pathNfilename.as_ref());
+        dc_get_abs_path(context, n.as_ptr())
    };

    if pathNfilename_abs.is_null() {
@@ -1523,6 +1518,51 @@ fn os_str_to_c_string_unicode(
    }
 }

+/// Convenience methods/associated functions for working with [CString]
+///
+/// This is helps transitioning from unsafe code.
+pub trait CStringExt {
+    /// Create a new [CString], yolo style
+    ///
+    /// This unwrap the result, panicking when there are embedded NULL
+    /// bytes.
+    fn yolo<T: Into<Vec<u8>>>(t: T) -> CString {
+        CString::new(t).expect("String contains null byte, can not be CString")
+    }
+}
+
+impl CStringExt for CString {}
+
+/// Convenience methods to make transitioning from raw C strings easier.
+///
+/// To interact with (legacy) C APIs we often need to convert from
+/// Rust strings to raw C strings.  This can be clumsy to do correctly
+/// and the compiler sometimes allows it in an unsafe way.  These
+/// methods make it more succinct and help you get it right.
+pub trait StrExt {
+    /// Allocate a new raw C `*char` version of this string.
+    ///
+    /// This allocates a new raw C string which must be freed using
+    /// `free`.  It takes care of some common pitfalls with using
+    /// [CString::as_ptr].
+    ///
+    /// [CString::as_ptr]: std::ffi::CString::as_ptr
+    ///
+    /// # Panics
+    ///
+    /// This function will panic when the original string contains an
+    /// interior null byte as this can not be represented in raw C
+    /// strings.
+    unsafe fn strdup(&self) -> *mut libc::c_char;
+}
+
+impl<T: AsRef<str>> StrExt for T {
+    unsafe fn strdup(&self) -> *mut libc::c_char {
+        let tmp = CString::yolo(self.as_ref());
+        dc_strdup(tmp.as_ptr())
+    }
+}
+
 /// Needs to free the result after use!
 pub unsafe fn to_cstring<S: AsRef<str>>(s: S) -> *mut libc::c_char {
    let cstr = CString::new(s.as_ref()).expect("invalid string converted");
@@ -2085,4 +2125,29 @@ mod tests {
        let ptr = some_path.as_ptr();
        assert_eq!(as_path_unicode(ptr), std::ffi::OsString::from("/some/path"));
    }
+
+    #[test]
+    fn test_cstring_yolo() {
+        assert_eq!(CString::new("hello").unwrap(), CString::yolo("hello"));
+    }
+
+    #[test]
+    fn test_strdup_str() {
+        unsafe {
+            let s = "hello".strdup();
+            let cmp = strcmp(s, b"hello\x00" as *const u8 as *const libc::c_char);
+            free(s as *mut libc::c_void);
+            assert_eq!(cmp, 0);
+        }
+    }
+
+    #[test]
+    fn test_strdup_string() {
+        unsafe {
+            let s = String::from("hello").strdup();
+            let cmp = strcmp(s, b"hello\x00" as *const u8 as *const libc::c_char);
+            free(s as *mut libc::c_void);
+            assert_eq!(cmp, 0);
+        }
+    }
 }
--- a/src/imap.rs
+++ b/src/imap.rs
@@ -1,3 +1,4 @@
+use std::ffi::CString;
 use std::net;
 use std::sync::{Arc, Condvar, Mutex, RwLock};
 use std::time::{Duration, SystemTime};
@@ -5,10 +6,9 @@ use std::time::{Duration, SystemTime};
 use crate::constants::*;
 use crate::context::Context;
 use crate::dc_loginparam::*;
-use crate::dc_tools::to_cstring;
+use crate::dc_tools::CStringExt;
 use crate::oauth2::dc_get_oauth2_access_token;
 use crate::types::*;
-use crate::x::free;

 pub const DC_IMAP_SEEN: usize = 0x0001;
 pub const DC_REGENERATE: usize = 0x01;
@@ -843,10 +843,8 @@ impl Imap {
                    .expect("missing message id");

                if 0 == unsafe {
-                    let message_id_c = to_cstring(message_id);
-                    let res = (self.precheck_imf)(context, message_id_c, folder.as_ref(), cur_uid);
-                    free(message_id_c as *mut _);
-                    res
+                    let message_id_c = CString::yolo(message_id);
+                    (self.precheck_imf)(context, message_id_c.as_ptr(), folder.as_ref(), cur_uid)
                } {
                    // check passed, go fetch the rest
                    if self.fetch_single_msg(context, &folder, cur_uid) == 0 {
--- a/src/log.rs
+++ b/src/log.rs
@@ -7,10 +7,9 @@ macro_rules! info {
        #[allow(unused_unsafe)]
        unsafe {
            let formatted = format!($msg, $($args),*);
-            let formatted_c =  $crate::dc_tools::to_cstring(formatted);
+            let formatted_c =  std::ffi::CString::new(formatted).unwrap();
            $ctx.call_cb($crate::constants::Event::INFO, $data1 as libc::uintptr_t,
-                     formatted_c as libc::uintptr_t);
-            libc::free(formatted_c as *mut libc::c_void);
+                     formatted_c.as_ptr() as libc::uintptr_t);
    }};
 }

@@ -23,10 +22,9 @@ macro_rules! warn {
        #[allow(unused_unsafe)]
        unsafe {
            let formatted = format!($msg, $($args),*);
-            let formatted_c = $crate::dc_tools::to_cstring(formatted);
+            let formatted_c = std::ffi::CString::new(formatted).unwrap();
            $ctx.call_cb($crate::constants::Event::WARNING, $data1 as libc::uintptr_t,
-                         formatted_c as libc::uintptr_t);
-            libc::free(formatted_c as *mut libc::c_void) ;
+                         formatted_c.as_ptr() as libc::uintptr_t);
        }};
 }

@@ -39,10 +37,9 @@ macro_rules! error {
        #[allow(unused_unsafe)]
        unsafe {
        let formatted = format!($msg, $($args),*);
-        let formatted_c = $crate::dc_tools::to_cstring(formatted);
+        let formatted_c = std::ffi::CString::new(formatted).unwrap();
        $ctx.call_cb($crate::constants::Event::ERROR, $data1 as libc::uintptr_t,
-                     formatted_c as libc::uintptr_t);
-        libc::free(formatted_c as *mut libc::c_void);
+                     formatted_c.as_ptr() as libc::uintptr_t);
    }};
 }

@@ -55,9 +52,8 @@ macro_rules! log_event {
        #[allow(unused_unsafe)]
        unsafe {
            let formatted = format!($msg, $($args),*);
-            let formatted_c = $crate::dc_tools::to_cstring(formatted);
+            let formatted_c = std::ffi::CString::new(formatted).unwrap();
            $ctx.call_cb($event, $data1 as libc::uintptr_t,
-                         formatted_c as libc::uintptr_t);
-            libc::free(formatted_c as *mut libc::c_void);
+                         formatted_c.as_ptr() as libc::uintptr_t);
    }};
 }
--- a/src/peerstate.rs
+++ b/src/peerstate.rs
@@ -462,13 +462,11 @@ mod tests {
    use super::*;
    use pretty_assertions::assert_eq;

-    use tempfile::{tempdir, TempDir};
-
-    use crate::context::*;
+    use tempfile::TempDir;

    #[test]
    fn test_peerstate_save_to_db() {
-        let ctx = unsafe { create_test_context() };
+        let ctx = crate::test_utils::dummy_context();
        let addr = "hello@mail.com";

        let pub_key = crate::key::Key::from_base64("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", KeyType::Public).unwrap();
@@ -506,26 +504,4 @@ mod tests {
        ctx: Context,
        dir: TempDir,
    }
-
-    unsafe extern "C" fn cb(
-        _context: &Context,
-        _event: Event,
-        _data1: libc::uintptr_t,
-        _data2: libc::uintptr_t,
-    ) -> libc::uintptr_t {
-        0
-    }
-
-    unsafe fn create_test_context() -> TestContext {
-        let mut ctx = dc_context_new(Some(cb), std::ptr::null_mut(), None);
-        let dir = tempdir().unwrap();
-        let dbfile = dir.path().join("db.sqlite");
-        assert!(
-            dc_open(&mut ctx, dbfile.to_str().unwrap(), None),
-            "Failed to open {}",
-            dbfile.to_str().unwrap()
-        );
-
-        TestContext { ctx: ctx, dir: dir }
-    }
 }
--- a/src/sql.rs
+++ b/src/sql.rs
@@ -10,7 +10,6 @@ use crate::dc_tools::*;
 use crate::error::{Error, Result};
 use crate::param::*;
 use crate::peerstate::*;
-use crate::x::*;

 const DC_OPEN_READONLY: usize = 0x01;

@@ -1049,9 +1048,8 @@ pub fn housekeeping(context: &Context) {
                    entry.file_name()
                );
                unsafe {
-                    let path = to_cstring(entry.path().to_str().unwrap());
-                    dc_delete_file(context, path);
-                    free(path as *mut _);
+                    let path = entry.path().to_c_string().unwrap();
+                    dc_delete_file(context, path.as_ptr());
                }
            }
        }