[FL-3927] FuriThread stdin (#3979)

* feat: FuriThread stdin
* ci: fix f18
* feat: stdio callback context

Co-authored-by: Georgii Surkov <37121527+gsurkov@users.noreply.github.com>
Co-authored-by: あく <alleteam@gmail.com>

furi/core/string.h

@@ -129,12 +129,12 @@ void furi_string_swap(FuriString* string_1, FuriString* string_2);
 
 /** Move string_2 content to string_1.
  *
- * Set the string to the other one, and destroy the other one.
+ * Copy data from one string to another and destroy the source.
  *
- * @param      string_1  The FuriString instance 1
- * @param      string_2  The FuriString instance 2
+ * @param      destination  The destination FuriString
+ * @param      source  The source FuriString
  */
-void furi_string_move(FuriString* string_1, FuriString* string_2);
+void furi_string_move(FuriString* destination, FuriString* source);
 
 /** Compute a hash for the string.
  *

furi/core/thread.c

@@ -23,12 +23,17 @@
 
 #define THREAD_MAX_STACK_SIZE (UINT16_MAX * sizeof(StackType_t))
 
-typedef struct FuriThreadStdout FuriThreadStdout;
-
-struct FuriThreadStdout {
+typedef struct {
     FuriThreadStdoutWriteCallback write_callback;
     FuriString* buffer;
-};
+    void* context;
+} FuriThreadStdout;
+
+typedef struct {
+    FuriThreadStdinReadCallback read_callback;
+    FuriString* unread_buffer; // <! stores data from `ungetc` and friends
+    void* context;
+} FuriThreadStdin;
 
 struct FuriThread {
     StaticTask_t container;
@@ -55,6 +60,7 @@ struct FuriThread {
     size_t heap_size;
 
     FuriThreadStdout output;
+    FuriThreadStdin input;
 
     // Keep all non-alignable byte types in one place,
     // this ensures that the size of this structure is minimal
@@ -136,6 +142,7 @@ static void furi_thread_body(void* context) {
 
 static void furi_thread_init_common(FuriThread* thread) {
     thread->output.buffer = furi_string_alloc();
+    thread->input.unread_buffer = furi_string_alloc();
 
     FuriThread* parent = NULL;
     if(xTaskGetSchedulerState() != taskSCHEDULER_NOT_STARTED) {
@@ -245,6 +252,7 @@ void furi_thread_free(FuriThread* thread) {
     }
 
     furi_string_free(thread->output.buffer);
+    furi_string_free(thread->input.unread_buffer);
     free(thread);
 }
 
@@ -710,13 +718,22 @@ uint32_t furi_thread_get_stack_space(FuriThreadId thread_id) {
 
 static size_t __furi_thread_stdout_write(FuriThread* thread, const char* data, size_t size) {
     if(thread->output.write_callback != NULL) {
-        thread->output.write_callback(data, size);
+        thread->output.write_callback(data, size, thread->output.context);
     } else {
         furi_log_tx((const uint8_t*)data, size);
     }
     return size;
 }
 
+static size_t
+    __furi_thread_stdin_read(FuriThread* thread, char* data, size_t size, FuriWait timeout) {
+    if(thread->input.read_callback != NULL) {
+        return thread->input.read_callback(data, size, timeout, thread->input.context);
+    } else {
+        return 0;
+    }
+}
+
 static int32_t __furi_thread_stdout_flush(FuriThread* thread) {
     FuriString* buffer = thread->output.buffer;
     size_t size = furi_string_size(buffer);
@@ -727,19 +744,33 @@ static int32_t __furi_thread_stdout_flush(FuriThread* thread) {
     return 0;
 }
 
-void furi_thread_set_stdout_callback(FuriThreadStdoutWriteCallback callback) {
-    FuriThread* thread = furi_thread_get_current();
-    furi_check(thread);
-    __furi_thread_stdout_flush(thread);
-    thread->output.write_callback = callback;
-}
-
 FuriThreadStdoutWriteCallback furi_thread_get_stdout_callback(void) {
     FuriThread* thread = furi_thread_get_current();
     furi_check(thread);
     return thread->output.write_callback;
 }
 
+FuriThreadStdinReadCallback furi_thread_get_stdin_callback(void) {
+    FuriThread* thread = furi_thread_get_current();
+    furi_check(thread);
+    return thread->input.read_callback;
+}
+
+void furi_thread_set_stdout_callback(FuriThreadStdoutWriteCallback callback, void* context) {
+    FuriThread* thread = furi_thread_get_current();
+    furi_check(thread);
+    __furi_thread_stdout_flush(thread);
+    thread->output.write_callback = callback;
+    thread->output.context = context;
+}
+
+void furi_thread_set_stdin_callback(FuriThreadStdinReadCallback callback, void* context) {
+    FuriThread* thread = furi_thread_get_current();
+    furi_check(thread);
+    thread->input.read_callback = callback;
+    thread->input.context = context;
+}
+
 size_t furi_thread_stdout_write(const char* data, size_t size) {
     FuriThread* thread = furi_thread_get_current();
     furi_check(thread);
@@ -772,6 +803,31 @@ int32_t furi_thread_stdout_flush(void) {
     return __furi_thread_stdout_flush(thread);
 }
 
+size_t furi_thread_stdin_read(char* buffer, size_t size, FuriWait timeout) {
+    FuriThread* thread = furi_thread_get_current();
+    furi_check(thread);
+
+    size_t from_buffer = MIN(furi_string_size(thread->input.unread_buffer), size);
+    size_t from_input = size - from_buffer;
+    size_t from_input_actual =
+        __furi_thread_stdin_read(thread, buffer + from_buffer, from_input, timeout);
+    memcpy(buffer, furi_string_get_cstr(thread->input.unread_buffer), from_buffer);
+    furi_string_right(thread->input.unread_buffer, from_buffer);
+
+    return from_buffer + from_input_actual;
+}
+
+void furi_thread_stdin_unread(char* buffer, size_t size) {
+    FuriThread* thread = furi_thread_get_current();
+    furi_check(thread);
+
+    FuriString* new_buf = furi_string_alloc(); // there's no furi_string_alloc_set_strn :(
+    furi_string_set_strn(new_buf, buffer, size);
+    furi_string_cat(new_buf, thread->input.unread_buffer);
+    furi_string_free(thread->input.unread_buffer);
+    thread->input.unread_buffer = new_buf;
+}
+
 void furi_thread_suspend(FuriThreadId thread_id) {
     furi_check(thread_id);
 

furi/core/thread.h

@@ -74,8 +74,23 @@ typedef int32_t (*FuriThreadCallback)(void* context);
  *
  * @param[in] data pointer to the data to be written to the standard out
  * @param[in] size size of the data in bytes
+ * @param[in] context optional context
  */
-typedef void (*FuriThreadStdoutWriteCallback)(const char* data, size_t size);
+typedef void (*FuriThreadStdoutWriteCallback)(const char* data, size_t size, void* context);
+
+/**
+ * @brief Standard input callback function pointer type
+ * 
+ * The function to be used as a standard input callback MUST follow this signature.
+ * 
+ * @param[out] buffer buffer to read data into
+ * @param[in] size maximum number of bytes to read into the buffer
+ * @param[in] timeout how long to wait for (in ticks) before giving up
+ * @param[in] context optional context
+ * @returns number of bytes that was actually read into the buffer
+ */
+typedef size_t (
+    *FuriThreadStdinReadCallback)(char* buffer, size_t size, FuriWait timeout, void* context);
 
 /**
  * @brief         State change callback function pointer type.
@@ -468,13 +483,30 @@ uint32_t furi_thread_get_stack_space(FuriThreadId thread_id);
  */
 FuriThreadStdoutWriteCallback furi_thread_get_stdout_callback(void);
 
+/**
+ * @brief Get the standard input callback for the current thead.
+ *
+ * @return pointer to the standard in callback function
+ */
+FuriThreadStdinReadCallback furi_thread_get_stdin_callback(void);
+
 /** Set standard output callback for the current thread.
  *
  * @param[in] callback pointer to the callback function or NULL to clear
+ * @param[in] context context to be passed to the callback
  */
-void furi_thread_set_stdout_callback(FuriThreadStdoutWriteCallback callback);
+void furi_thread_set_stdout_callback(FuriThreadStdoutWriteCallback callback, void* context);
+
+/** Set standard input callback for the current thread.
+ * 
+ * @param[in] callback pointer to the callback function or NULL to clear
+ * @param[in] context context to be passed to the callback
+ */
+void furi_thread_set_stdin_callback(FuriThreadStdinReadCallback callback, void* context);
 
 /** Write data to buffered standard output.
+ * 
+ * @note You can also use the standard C `putc`, `puts`, `printf` and friends.
  * 
  * @param[in] data pointer to the data to be written
  * @param[in] size data size in bytes
@@ -489,6 +521,29 @@ size_t furi_thread_stdout_write(const char* data, size_t size);
  */
 int32_t furi_thread_stdout_flush(void);
 
+/** Read data from the standard input
+ * 
+ * @note You can also use the standard C `getc`, `gets` and friends.
+ * 
+ * @param[in] buffer pointer to the buffer to read data into
+ * @param[in] size how many bytes to read into the buffer
+ * @param[in] timeout how long to wait for (in ticks) before giving up
+ * @return number of bytes that was actually read
+ */
+size_t furi_thread_stdin_read(char* buffer, size_t size, FuriWait timeout);
+
+/** Puts data back into the standard input buffer
+ * 
+ * `furi_thread_stdin_read` will return the bytes in the same order that they
+ * were supplied to this function.
+ * 
+ * @note You can also use the standard C `ungetc`.
+ * 
+ * @param[in] buffer pointer to the buffer to get data from
+ * @param[in] size how many bytes to read from the buffer
+ */
+void furi_thread_stdin_unread(char* buffer, size_t size);
+
 /**
  * @brief Suspend a thread.
  *