util/gmime-extra: add g_mime_stream_gzfile_{new, open}

These are usable as standard GMime streams, and transparently
decompress gzipped files.

diff --git a/util/gmime-extra.c b/util/gmime-extra.c
index 4b577a5b1cc7457fa11e128615a2ddff3580467d..7562d9062a20ab1b1a2a9c917c3d4e9b56afe7f5 100644 (file)
--- a/util/gmime-extra.c
+++ b/util/gmime-extra.c
@@ -1,6 +1,63 @@
 #include "gmime-extra.h"
 #include <string.h>
 
+static
+GMimeStream *
+_gzfile_maybe_filter (GMimeStream *file_stream) {
+    char buf[4];
+    int bytes_read;
+
+    if ((bytes_read = g_mime_stream_read (file_stream, buf, sizeof (buf))) < 0)
+       return NULL;
+
+    if (g_mime_stream_reset (file_stream))
+       return NULL;
+
+    /* check for gzipped input */
+    if (bytes_read >= 2 && buf[0] == 0x1f && (unsigned char)buf[1] == 0x8b) {
+       GMimeStream *gzstream;
+       GMimeFilter *gzfilter;
+
+       gzfilter = g_mime_filter_gzip_new (GMIME_FILTER_GZIP_MODE_UNZIP, 0);
+       if (! gzfilter)
+           return NULL;
+
+       gzstream = g_mime_stream_filter_new (file_stream);
+       if (! gzstream)
+           return NULL;
+
+       /* ignore filter id */
+       (void)g_mime_stream_filter_add ((GMimeStreamFilter *)gzstream, gzfilter);
+       return gzstream;
+    } else {
+       return file_stream;
+    }
+}
+
+GMimeStream *
+g_mime_stream_gzfile_new (int fd)
+{
+    GMimeStream *file_stream;
+
+    file_stream = g_mime_stream_fs_new (fd);
+    if (! file_stream)
+       return NULL;
+
+    return _gzfile_maybe_filter (file_stream);
+}
+
+GMimeStream *
+g_mime_stream_gzfile_open (const char *filename)
+{
+    GMimeStream *file_stream;
+
+    file_stream = g_mime_stream_fs_open (filename, 0, 0, NULL);
+    if (! file_stream)
+       return NULL;
+
+    return _gzfile_maybe_filter (file_stream);
+}
+
 GMimeStream *
 g_mime_stream_stdout_new()
 {

diff --git a/util/gmime-extra.h b/util/gmime-extra.h
index a42e43e72c01f16824c142b786875089f8630e6b..b0c8d3d84a07429a44d84c5c7f1c03780b3bee51 100644 (file)
--- a/util/gmime-extra.h
+++ b/util/gmime-extra.h
@@ -9,6 +9,14 @@ extern "C" {
 
 GMimeStream *g_mime_stream_stdout_new(void);
 
+/* Return a GMime stream for this open file descriptor, un-gzipping if
+ * necessary */
+GMimeStream *g_mime_stream_gzfile_new (int fd);
+
+/* Return a GMime stream for this path, un-gzipping if
+ * necessary */
+GMimeStream *g_mime_stream_gzfile_open (const char *filename);
+
 /**
  * Get last 16 hex digits of fingerprint ("keyid")
  */