* extract based on filename regexp and document it

man/mu-extract.1

@@ -1,4 +1,4 @@
-.TH MU EXTRACT 1 "April 2011" "User Manuals"
+.TH MU EXTRACT 1 "May 2011" "User Manuals"
 
 .SH NAME 
 
@@ -6,8 +6,8 @@ mu extract\- display and save message parts (attachments)
 
 .SH SYNOPSIS
 
-.B mu extract [options] <file> [<parts-to-save>]
+.B mu extract [options] <file>
-.B mu extract [options] <file> <filename>
+.B mu extract [options] <file> <pattern>
 
 .SH DESCRIPTION
 
@@ -16,11 +16,12 @@ attachments) from mail messages. It works on message files, and does not
 require the message to be indexed.
 
 For attachments, the file name used for saving is the name of the attachment
-in the message. If there is no such name, or when saving other mime-parts, a
+in the message. If there is no such name, or when saving other MIME-parts, a
-name derived from the message-id of the message.
+name is derived from the message-id of the message.
 
-If you specify a filename as the second argument, an attempt will be made to
+If you specify a pattern (a case-insensitive regular expression)as the second
-find a extract the particular (first) MIME-part with that filename.
+argument, all attachments with filenames matching that pattern will be
+extracted.
 
 Without any options, \fBmu extract\fR simply outputs the list of MIME-parts in
 the message.
@@ -56,6 +57,24 @@ allowed.
 application for the particular file type. Depends on the \fBxdg-open\fR
 utility.
 
+.SH EXAMPLES
+
+To display information about all the MIME-parts in a message file:
+.nf
+   $ mu extract msgfile
+.fi
+
+To extract MIME-part 3 and 4 from this message, overwriting existing files
+with the same name:
+.nf
+   $ mu extract --parts=3,4 --overwrite msgfile
+.fi
+
+To extract all files ending in '.jpg' (case-insensitive):
+.nf
+   $ mu extract msgfile '.*\.jpg'
+.fi
+
 .SH BUGS
 
 Please report bugs if you find them:

src/mu-cmd-extract.c

@@ -1,3 +1,5 @@
+/* -*-mode: c; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-*/
+
 /*
 ** Copyright (C) 2010-2011 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
 **
@@ -22,6 +24,7 @@
 #endif /*HAVE_CONFIG_H*/
 
 #include <stdlib.h>
+#include <string.h>
 
 #include "mu-msg.h"
 #include "mu-msg-part.h"
@@ -94,22 +97,60 @@ save_numbered_parts (MuMsg *msg, MuConfig *opts)
 	return rv;
 }
 
-static gboolean
+static GRegex*
-save_part_with_filename (MuMsg *msg, const char *filename, MuConfig *opts)
+anchored_regex (const char* pattern)
 {
-	int idx;
+	GRegex *rx;
+	GError *err;
+	gchar *anchored;
 
-	idx = mu_msg_part_find_file (msg, filename);
+	
-	if (idx == -1) {
+	anchored = g_strdup_printf
-		g_warning ("file '%s' not found in this message", filename);
+		("%s%s%s",
+		 pattern[0] == '^' ? "" : "^",
+		 pattern,
+		 pattern[strlen(pattern)-1] == '$' ? "" : "$");
+
+	err = NULL;
+	rx = g_regex_new (anchored, G_REGEX_CASELESS|G_REGEX_OPTIMIZE, 0,
+			  &err);
+	g_free (anchored);
+
+	if (!rx) {
+		g_warning ("error in regular expression '%s': %s",
+			   pattern, err->message);
+		g_error_free (err);
+		return NULL;
+	}
+	
+	return rx;
+}
+
+
+static gboolean
+save_part_with_filename (MuMsg *msg, const char *pattern, MuConfig *opts)
+{
+	GSList *lst, *cur;
+	GRegex *rx;
+	gboolean rv;
+
+	/* 'anchor' the pattern with '^...$' if not already */
+	rx = anchored_regex (pattern);
+	if (!rx)
+		return FALSE;
+	
+	lst = mu_msg_part_find_files (msg, rx);
+	g_regex_unref (rx);
+	if (!lst) {
+		g_warning ("no matching attachments found");
 		return FALSE;
 	}
 
-	if (!save_part (msg, opts->targetdir, idx, opts->overwrite,
+	for (cur = lst, rv = TRUE; cur; cur = g_slist_next (cur))
-			opts->play)) 
+		rv &= save_part (msg, opts->targetdir,
-		return FALSE;
+				 GPOINTER_TO_UINT(cur->data),
-	
+				 opts->overwrite, opts->play);
-	return TRUE;
+	return rv;
 }
 
 
@@ -180,9 +221,6 @@ save_part_if (MuMsg *msg, MuMsgPart *part, SaveData *sd)
 	++sd->saved_num;
 
 leave:
-	if (!sd->result) 
-		g_warning ("failed to save/play MIME-part %u to %s",
-			   part->index, filepath ? filepath : "<none>");
 	sd->result = rv;
 	g_free (filepath);
 }
@@ -292,12 +330,13 @@ static gboolean
 check_params (MuConfig *opts)
 {
 	if (!opts->params[1] || (opts->params[2] && opts->params[3])) {
-		g_warning ("usage: mu extract [options] <file> [<filename>]");
+		g_warning ("usage: mu extract [options] <file> [<pattern>]");
-		return FALSE;
+		return MU_EXITCODE_ERROR;
 	}
 
+	
 	if (opts->params[2] && (opts->save_attachments || opts->save_all)) {
-		g_warning ("--save-attachments --save-all is allowed don't accept "
+		g_warning ("--save-attachments --save-all don't accept "
 			   "a filename");
 		return FALSE;
 	}
@@ -329,11 +368,9 @@ mu_cmd_extract (MuConfig *opts)
 	if (!check_params (opts))
 		return MU_EXITCODE_ERROR;
 	
-	if (!opts->params[2] &&
+	if (!opts->params[2] && !opts->parts &&
-	    !opts->parts &&
+	    !opts->save_attachments && !opts->save_all) 
-	    !opts->save_attachments &&
+		rv = show_parts (opts->params[1], opts); /* show, don't save */
-	    !opts->save_all)  /* show, don't save */
-		rv = show_parts (opts->params[1], opts);
 	else {
 		rv = mu_util_check_dir(opts->targetdir, FALSE, TRUE);
 		if (!rv)

src/mu-msg-part.c

@@ -62,12 +62,12 @@ find_part (MuMsg* msg, guint partidx)
 }
 
 struct _PartData {
-	MuMsg					*_msg;
+	MuMsg			*_msg;
-	unsigned				_idx;
+	unsigned		_idx;
 	MuMsgPartForeachFunc	_func;
-	gpointer				_user_data;
+	gpointer		_user_data;
 };
-typedef struct _PartData		PartData;
+typedef struct _PartData PartData;
 
 
 static void
@@ -106,7 +106,7 @@ mu_msg_part_foreach (MuMsg *msg, MuMsgPartForeachFunc func,
 
 	pdata._msg       = msg;
 	pdata._idx       = 0;
-	pdata._func		 = func;
+	pdata._func	 = func;
 	pdata._user_data = user_data;
 	
 	g_mime_message_foreach (msg->_file->_mime_msg,
@@ -320,7 +320,7 @@ mu_msg_part_find_cid (MuMsg *msg, const char* sought_cid)
 {
 	const char* cid;
 		
-	g_return_val_if_fail (msg, -1L);
+	g_return_val_if_fail (msg, -1);
 	g_return_val_if_fail (sought_cid, -1);
 		
 	cid = g_str_has_prefix (sought_cid, "cid:") ?
@@ -331,32 +331,50 @@ mu_msg_part_find_cid (MuMsg *msg, const char* sought_cid)
 				  (gpointer)cid);
 }
 
+struct _MatchData2 {
+	GSList       *_lst;
+	const GRegex *_rx;
+	guint         _idx;
+};
+typedef struct _MatchData2 MatchData2;
 
-static gboolean
+
-match_filename (GMimeObject *part, const char *sought_filename)
+static void
+match_filename_rx (GMimeObject *parent, GMimeObject *part, MatchData2 *mdata)
 {
 	const char *fname;
 	
 	if (!GMIME_IS_PART(part))
-		return FALSE;
+		goto leave;
 	
 	fname = g_mime_part_get_filename (GMIME_PART(part));
 	if (!fname)
-		return FALSE;
+		goto leave;
 	
-	return g_strcmp0 (fname, sought_filename) == 0 ? TRUE : FALSE;
+	if (g_regex_match (mdata->_rx, fname, 0, NULL))
+		mdata->_lst = g_slist_prepend (mdata->_lst,
+					       GUINT_TO_POINTER(mdata->_idx));
+leave:
+	++mdata->_idx;
 }
 
 
-int
+GSList*
-mu_msg_part_find_file (MuMsg *msg, const char* sought_filename)
+mu_msg_part_find_files (MuMsg *msg, const GRegex *pattern)
 {
-	g_return_val_if_fail (msg, -1);
+	MatchData2 mdata;
-	g_return_val_if_fail (sought_filename, -1);
 	
-	return msg_part_find_idx (msg->_file->_mime_msg,
+	g_return_val_if_fail (msg, NULL);
-				  (MatchFunc)match_filename,
+	g_return_val_if_fail (pattern, NULL);
-				  (gpointer)sought_filename);
+
+	mdata._lst = NULL;
+	mdata._rx  = pattern;
+	mdata._idx = 0;
+	
+	g_mime_message_foreach (msg->_file->_mime_msg,
+				(GMimeObjectForeachFunc)match_filename_rx,
+				&mdata);
+	return mdata._lst;
 }
 
 

src/mu-msg-part.h

@@ -153,15 +153,16 @@ 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
+ * retrieve a list of indices for mime-parts with filenames matching a regex
- * filename
  *  
  * @param msg a message
- * @param sought_filename filename to look for
+ * @param a regular expression to match the filename with
  * 
- * @return the part index number of the found part, or -1 if it was not found
+ * @return a list with indices for the files matching the pattern; the
+ * indices are the GPOINTER_TO_UNIT(lst->data) of the list. The must
+ * be freed with g_slist_free
  */
-int mu_msg_part_find_file (MuMsg *msg, const char* sought_filename);
+GSList* mu_msg_part_find_files (MuMsg *msg, const GRegex *pattern);
 
 
 typedef void (*MuMsgPartForeachFunc) (MuMsg*, MuMsgPart*, gpointer);

www/cheatsheet.org

@@ -28,7 +28,7 @@ Here are some tips for using =mu=. If you want to know more, please refer to the
    After you have indexed your messages, you can search them. Here are some
    examples.
 
-*** messages about Helsinki
+*** messages about Helsinki (in message body, subject, sender, ...)
 
 #+begin_src sh
    $ mu find Helsinki
@@ -52,6 +52,26 @@ Here are some tips for using =mu=. If you want to know more, please refer to the
    $ mu find 'subject:soc*' flag:unread
 #+end_src
 
+** Retrieving attachments from messages
+   
+
+   You can retrieve attachments from messages using =mu extract=, which takes a
+   message file as an argument. Without any other arguments, it displays the
+   MIME-parts of the message. You can then get specific attachments:
+
+#+begin_src sh
+   $ mu extract --parts=3,4 my-msg-file
+#+end_src
+
+   will get you parts 3 and 4. You can also extract files based on their name:
+
+#+begin_src sh
+   $ mu extract my-msg-file '.*\.jpg'
+#+end_src
+
+   The second argument is a case-insensitive regular expression, and the command
+   will extract any files matching the pattern -- in the example, all
+   =.jpg=-files.
    
 
 
@@ -75,7 +95,7 @@ Here are some tips for using =mu=. If you want to know more, please refer to the
    
 ** Integration with mail clients
 
-  See the example in the =mu-find= man page.
+  The =mu-find= man page contains examples for =mutt= and =wanderlust=.
 
 #+html:<hr/><div align="center">&copy; 2011 Dirk-Jan C. Binnema</div>
 #+begin_html