Add provider info functions to the FFI API

A lot of work from @Hocuri and @Simon-Laux mostly.

This exposes the API of the deltachat-provider-overview crate on the
deltachat FFI API, allowing clients to use it to help users set up
their accounts.

deltachat-ffi/Cargo.toml

@@ -16,6 +16,7 @@ crate-type = ["cdylib", "staticlib"]
 
 [dependencies]
 deltachat = { path = "../", default-features = false }
+deltachat-provider-overview = { git = "https://github.com/deltachat/provider-overview", rev = "366b41a7503973e4ffac3aa5173b419f2f03c211" }
 libc = "0.2"
 human-panic = "1.0.1"
 num-traits = "0.2.6"

deltachat-ffi/deltachat.h

@@ -442,7 +442,112 @@ char*           dc_get_info                  (dc_context_t* context);
  */
 char*           dc_get_oauth2_url            (dc_context_t* context, const char* addr, const char* redirect_uri);
 
+/**
+ * Opaque object containing information about one single email provider.
+ */
+typedef struct _dc_provider  dc_provider_t;
 
+/**
+ * Create a provider struct for the given domain.
+ *
+ * @param doamin The domain to get provider info for.
+ * @return a dc_provider_t struct which can be used with the dc_provider_get_*
+ *     accessor functions.  If no provider info is found, NULL will be
+ *     returned.
+ */
+dc_provider_t*  dc_provider_new_from_domain           (char* domain);
+
+/**
+ * Create a provider struct for the given email address.
+ *
+ * The provider is extracted from the email address and it's information is returned.
+ *
+ * @param email The user's email address to extract the provider info form.
+ * @return a dc_provider_t struct which can be used with the dc_provider_get_*
+ *     accessor functions.  If no provider info is found, NULL will be
+ *     returned.
+ */
+dc_provider_t*  dc_provider_new_from_email            (char* email);
+
+/**
+ * URL of the overview page.
+ *
+ * This URL allows linking to the providers page on providers.delta.chat.
+ *
+ * @param provider The dc_provider_t struct.
+ * @return A string which must be free()d.
+ */
+char*           dc_provider_get_overview_page         (const dc_provider_t* provider);
+
+/**
+ * The provider's name.
+ *
+ * The name of the provider, e.g. "POSTEO".
+ *
+ * @param provider The dc_provider_t struct.
+ * @return A string which must be free()d.
+ */
+char*           dc_provider_get_name                  (const dc_provider_t* provider);
+
+/**
+ * The markdown content of the providers page.
+ *
+ * This contains the preparation steps or additional information if the status
+ * is DC_PROVIDER_STATUS_BROKEN.
+ *
+ * @param provider The dc_provider_t struct.
+ * @return A string which must be free()d.
+ */
+char*           dc_provider_get_markdown              (const dc_provider_t* provider);
+
+/**
+ * Date of when the state was last checked/updated.
+ *
+ * This is returned as a string.
+ *
+ * @param provider The dc_provider_t struct.
+ * @return A string which must be free()d.
+ */
+char*           dc_provider_get_status_date           (const dc_provider_t* provider);
+
+/**
+ * Whether DC works with this provider.
+ *
+ * Can be one of @ref DC_PROVIDER_STATUS_OK, @ref
+ * DC_PROVIDER_STATUS_PREPARATION and @ref DC_PROVIDER_STATUS_BROKEN.
+ *
+ * @param provider The dc_provider_t struct.
+ * @return The status as a constant number.
+ */
+int             dc_provider_get_status                (const dc_provider_t* provider);
+
+/**
+ * Free the provider info struct.
+ *
+ * @param provider The dc_provider_t struct.
+ */
+void            dc_provider_unref                     (const dc_provider_t* provider);
+
+/**
+ * Provider status returned by dc_provider_get_status().
+ *
+ * Works right out of the box without any preperation steps needed
+ */
+#define         DC_PROVIDER_STATUS_OK           1
+
+/**
+ * Provider status returned by dc_provider_get_status().
+ *
+ * Works, but preparation steps are needed
+ */
+#define         DC_PROVIDER_STATUS_PREPARATION  2
+
+/**
+ * Provider status returned by dc_provider_get_status().
+ *
+ * Doesn't work (too unstable to use falls also in this category)
+ */
+#define         DC_PROVIDER_STATUS_BROKEN       3
 
 // connect
 

deltachat-ffi/src/lib.rs

@@ -2813,6 +2813,8 @@ fn as_opt_str<'a>(s: *const libc::c_char) -> Option<&'a str> {
     Some(dc_tools::as_str(s))
 }
 
+pub mod providers;
+
 pub trait ResultExt<T> {
     fn unwrap_or_log_default(self, context: &context::Context, message: &str) -> T;
     fn log_err(&self, context: &context::Context, message: &str);

deltachat-ffi/src/providers.rs

@@ -0,0 +1,92 @@
+extern crate deltachat_provider_overview;
+
+use std::ptr;
+
+use deltachat::dc_tools::{as_str, StrExt};
+use deltachat_provider_overview::StatusState;
+
+#[no_mangle]
+pub type dc_provider_t = deltachat_provider_overview::Provider;
+
+#[no_mangle]
+pub unsafe extern "C" fn dc_provider_new_from_domain(
+    domain: *const libc::c_char,
+) -> *const dc_provider_t {
+    match deltachat_provider_overview::get_provider_info(as_str(domain)) {
+        Some(provider) => provider,
+        None => ptr::null(),
+    }
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn dc_provider_new_from_email(
+    email: *const libc::c_char,
+) -> *const dc_provider_t {
+    let domain = deltachat_provider_overview::get_domain_from_email(as_str(email));
+    match deltachat_provider_overview::get_provider_info(domain) {
+        Some(provider) => provider,
+        None => ptr::null(),
+    }
+}
+
+macro_rules! null_guard {
+    ($context:tt) => {
+        if $context.is_null() {
+            return ptr::null_mut() as *mut libc::c_char;
+        }
+    };
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn dc_provider_get_overview_page(
+    provider: *const dc_provider_t,
+) -> *mut libc::c_char {
+    null_guard!(provider);
+    format!(
+        "{}/{}",
+        deltachat_provider_overview::PROVIDER_OVERVIEW_URL,
+        (*provider).overview_page
+    )
+    .strdup()
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn dc_provider_get_name(provider: *const dc_provider_t) -> *mut libc::c_char {
+    null_guard!(provider);
+    (*provider).name.strdup()
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn dc_provider_get_markdown(
+    provider: *const dc_provider_t,
+) -> *mut libc::c_char {
+    null_guard!(provider);
+    (*provider).markdown.strdup()
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn dc_provider_get_status_date(
+    provider: *const dc_provider_t,
+) -> *mut libc::c_char {
+    null_guard!(provider);
+    (*provider).status.date.strdup()
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn dc_provider_get_status(provider: *const dc_provider_t) -> u32 {
+    if provider.is_null() {
+        return 0;
+    }
+    match (*provider).status.state {
+        StatusState::OK => 1,
+        StatusState::PREPARATION => 2,
+        StatusState::BROKEN => 3,
+    }
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn dc_provider_unref(_provider: *const dc_provider_t) {
+    ()
+}
+
+// TODO expose general provider overview url?