* implement saving mime-part by file-name, improve error handling

src/mu-cmd-extract.c

@@ -33,17 +33,21 @@ static gboolean
 save_part (MuMsg *msg, const char *targetdir, guint partidx, gboolean overwrite,
 	   gboolean play)
 {
+	GError *err;
 	gchar *filepath;
 	
 	filepath = mu_msg_part_filepath (msg, targetdir, partidx);
 	if (!filepath) {
-		g_warning ("%s: failed to get filepath", __FUNCTION__);
+		g_warning ("failed to get filepath");
 		return FALSE;
 	}
 
-	if (!mu_msg_part_save (msg, filepath, partidx, overwrite, FALSE)) {
+	err = NULL;
-		g_warning ("%s: failed to save MIME-part %d at %s",
+	if (!mu_msg_part_save (msg, filepath, partidx, overwrite, FALSE, &err)) {
-			   __FUNCTION__, partidx, filepath);
+		g_warning ("failed to save MIME-part: %s",
+			   err&&err->message ? err->message : "error");
+		if (err)
+			g_error_free (err);
 		g_free (filepath);
 		return FALSE;
 	}
@@ -51,6 +55,7 @@ save_part (MuMsg *msg, const char *targetdir, guint partidx, gboolean overwrite,
 	if (play)
 		mu_util_play (filepath, TRUE, FALSE);
 
+	g_free (filepath);	
 	return TRUE;
 }
 
@@ -89,6 +94,26 @@ save_numbered_parts (MuMsg *msg, MuConfig *opts)
 	return rv;
 }
 
+static gboolean
+save_part_with_filename (MuMsg *msg, const char *filename, MuConfig *opts)
+{
+	int idx;
+
+	idx = mu_msg_part_find_file (msg, filename);
+	if (idx == -1) {
+		g_warning ("file '%s' not found in this message", filename);
+		return FALSE;
+	}
+		
+	if (!save_part (msg, opts->targetdir, idx, opts->overwrite,
+			opts->play)) 
+		return FALSE;
+	
+	return TRUE;
+}
+
+
+
 struct _SaveData {
 	gboolean		 attachments_only;
 	gboolean		 result;
@@ -126,6 +151,7 @@ save_part_if (MuMsg *msg, MuMsgPart *part, SaveData *sd)
 {
 	gchar *filepath;
 	gboolean rv;
+	GError *err;
 	
 	if (ignore_part (msg, part, sd))
 		return;
@@ -137,9 +163,15 @@ save_part_if (MuMsg *msg, MuMsgPart *part, SaveData *sd)
 	if (!filepath) 
 		goto leave;
 
+	err = NULL;
 	if (!mu_msg_part_save (msg, filepath, part->index,
-			       sd->overwrite, FALSE))
+			       sd->overwrite, FALSE, &err)) {
+		g_warning ("failed to save MIME-part: %s",
+			   err&&err->message ? err->message : "error");
+		if (err)
+			g_error_free (err);
 		goto leave;
+	}
 	
 	if (sd->play &&  !mu_util_play (filepath, TRUE, FALSE))
 		goto leave;
@@ -183,7 +215,7 @@ save_certain_parts (MuMsg *msg, gboolean attachments_only,
 
 
 static gboolean
-save_parts (const char *path, MuConfig *opts)
+save_parts (const char *path, const char *filename, MuConfig *opts)
 {	
 	MuMsg* msg;
 	gboolean rv;
@@ -203,6 +235,8 @@ save_parts (const char *path, MuConfig *opts)
 	/* should we save some explicit parts? */
 	if (opts->parts)
 		rv = save_numbered_parts (msg, opts);
+	else if (filename)
+		rv = save_part_with_filename (msg, filename, opts);
 	else if (opts->save_attachments)  /* all attachments */
 		rv = save_certain_parts (msg, TRUE,
 					 opts->targetdir, opts->overwrite,
@@ -257,8 +291,14 @@ show_parts (const char* path, MuConfig *opts)
 static gboolean
 check_params (MuConfig *opts)
 {
-	if (!opts->params[1] || opts->params[2]) {
+	if (!opts->params[1] || (opts->params[2] && opts->params[3])) {
-		g_warning ("usage: mu extract [options] <file>");
+		g_warning ("usage: mu extract [options] <file> [<filename>]");
+		return FALSE;
+	}
+
+	if (opts->params[2] && (opts->save_attachments || opts->save_all)) {
+		g_warning ("--save-attachments --save-all is allowed don't accept "
+			   "a filename");
 		return FALSE;
 	}
 	
@@ -289,7 +329,8 @@ mu_cmd_extract (MuConfig *opts)
 	if (!check_params (opts))
 		return MU_EXITCODE_ERROR;
 	
-	if (!opts->parts &&
+	if (!opts->params[2] &&
+	    !opts->parts &&
 	    !opts->save_attachments &&
 	    !opts->save_all)  /* show, don't save */
 		rv = show_parts (opts->params[1], opts);
@@ -299,7 +340,9 @@ mu_cmd_extract (MuConfig *opts)
 			g_warning ("target '%s' is not a writable directory",
 				   opts->targetdir);
 		else
-			rv = save_parts (opts->params[1], opts); /* save */
+			rv = save_parts (opts->params[1],
+					 opts->params[2],
+					 opts); /* save */
 	}
 		
 	return rv ? MU_EXITCODE_OK : MU_EXITCODE_ERROR;

src/mu-msg-part.c

@@ -1,3 +1,5 @@
+/* -*-mode: c; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-*/
+
 /*
 ** Copyright (C) 2008-2011 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
 **
@@ -149,7 +151,7 @@ write_to_stream (GMimeObject *part, int fd)
 
 gboolean
 save_part (GMimeObject *part, const char *fullpath,
-		   gboolean overwrite, gboolean use_existing)
+	   gboolean overwrite, gboolean use_existing, GError **err)
 {
 	int fd;
 	gboolean rv;
@@ -161,13 +163,20 @@ save_part (GMimeObject *part, const char *fullpath,
 		
 	/* ok, try to create the file */
 	fd = mu_util_create_writeable_fd (fullpath, 0600, overwrite);
-		if (fd == -1)
+	if (fd == -1) {
+		g_set_error (err, 0, MU_ERROR_FILE,
+			     "could not open '%s' for writing: %s",
+			     fullpath, errno ? strerror(errno) : "error");
 		return FALSE;
+	}		
 
 	rv = write_to_stream (part, fd);
-		if (close (fd) != 0)
+	if (close (fd) != 0) {
-				g_warning ("%s: failed to close %s: %s", __FUNCTION__,
+		g_set_error (err, 0, MU_ERROR_FILE,
-						   fullpath, strerror(errno));
+			     "could not close '%s': %s",
+			     fullpath, errno ? strerror(errno) : "error");
+		return FALSE;
+	}
 
 	return TRUE;
 }
@@ -238,7 +247,7 @@ mu_msg_part_filepath_cache (MuMsg *msg, guint partid)
 
 gboolean
 mu_msg_part_save (MuMsg *msg, const char *fullpath, guint partidx,
-				  gboolean overwrite, gboolean use_cached)
+		  gboolean overwrite, gboolean use_cached, GError **err)
 {
 	GMimeObject *part;
 		
@@ -248,21 +257,17 @@ mu_msg_part_save (MuMsg *msg, const char *fullpath, guint partidx,
 		
 	part = find_part (msg, partidx);
 	if (!GMIME_IS_PART(part)) {
-				g_warning ("%s: cannot find part %u", __FUNCTION__, partidx);
+		g_set_error (err, 0, MU_ERROR_GMIME,
+			     "cannot find part %u", partidx);
 		return FALSE;
 	}
 				
-		if (!save_part (part, fullpath, overwrite, use_cached)) {
+	if (!save_part (part, fullpath, overwrite, use_cached, err))
-				g_warning ("%s: failed to save '%s'", __FUNCTION__, fullpath);
 		return FALSE;
-		}
 
 	return TRUE;
 }
 
-
-
-
 typedef gboolean (*MatchFunc) (GMimeObject *part, gpointer data);
 
 struct _MatchData {
@@ -327,6 +332,35 @@ mu_msg_part_find_cid (MuMsg *msg, const char* sought_cid)
 }
 
 
+static gboolean
+match_filename (GMimeObject *part, const char *sought_filename)
+{
+	const char *fname;
+
+	if (!GMIME_IS_PART(part))
+		return FALSE;
+	
+	fname = g_mime_part_get_filename (GMIME_PART(part));
+	if (!fname)
+		return FALSE;
+	
+	return g_strcmp0 (fname, sought_filename) == 0 ? TRUE : FALSE;
+}
+
+
+int
+mu_msg_part_find_file (MuMsg *msg, const char* sought_filename)
+{
+	g_return_val_if_fail (msg, -1);
+	g_return_val_if_fail (sought_filename, -1);
+		
+	return msg_part_find_idx (msg->_file->_mime_msg,
+				  (MatchFunc)match_filename,
+				  (gpointer)sought_filename);
+}
+
+
+
 gboolean
 mu_msg_part_looks_like_attachment (MuMsgPart *part, gboolean include_inline)
 {

src/mu-msg-part.h

@@ -1,3 +1,5 @@
+/* -*-mode: c; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-*/
+
 /*
 ** Copyright (C) 2008-2010 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
 **
@@ -101,11 +103,12 @@ gboolean mu_msg_part_looks_like_attachment (MuMsgPart *part,
  * @param partidx index of the attachment you want to save
  * @param overwrite overwrite existing files?
  * @param don't raise error when the file already exists
+ * @param err receives error information (when function returns NULL)
  * 
  * @return full path to the message part saved or NULL in case or error; free with g_free
  */
 gboolean mu_msg_part_save (MuMsg *msg, const char *filepath, guint partidx,
-			   gboolean overwrite, gboolean use_cached);
+			   gboolean overwrite, gboolean use_cached, GError **err);
 
 
 /**
@@ -138,7 +141,7 @@ gchar* mu_msg_part_filepath_cache (MuMsg *msg, guint partid)
 
 
 /**
- * get the part inede for the message part with a certain content-id
+ * get the part index for the message part with a certain content-id
  * 
  * @param msg a message
  * @param content_id a content-id to search
@@ -147,10 +150,19 @@ gchar* mu_msg_part_filepath_cache (MuMsg *msg, guint partid)
  */
 int mu_msg_part_find_cid (MuMsg *msg, const char* content_id);
 
+/**
+ * get the (first) part index for the message part with a certain
+ * filename
+ * 
+ * @param msg a message
+ * @param sought_filename filename to look for
+ * 
+ * @return the part index number of the found part, or -1 if it was not found
+ */
+int mu_msg_part_find_file (MuMsg *msg, const char* sought_filename);
 
 
 typedef void (*MuMsgPartForeachFunc) (MuMsg*, MuMsgPart*, gpointer);
-
 /**
  * call a function for each of the mime part in a message 
  *