1 files changed, 37 insertions, 1 deletions

diff --git a/ui-snapshot.c b/ui-snapshot.c
index eb5f1cd..649569f 100644
--- a/ui-snapshot.c
+++ b/ui-snapshot.c
@@ -1,65 +1,101 @@
 /* ui-snapshot.c: generate snapshot of a commit
  *
  * Copyright (C) 2006 Lars Hjemli
  *
  * Licensed under GNU General Public License v2
  *   (see COPYING for full license text)
  */
 
 #include "cgit.h"
 
+static int write_tar_gzip_archive(struct archiver_args *args)
+{
+    int rw[2];
+    pid_t gzpid;
+    int stdout2;
+    int status;
+    int rv;
+
+    stdout2 = chk_non_negative(dup(STDIN_FILENO), "Preserving STDOUT before compressing");
+    chk_zero(pipe(rw), "Opening pipe from compressor subprocess");
+    gzpid = chk_non_negative(fork(), "Forking compressor subprocess");
+    if(gzpid==0) {
+            /* child */
+            chk_zero(close(rw[1]), "Closing write end of pipe in child");
+            chk_zero(close(STDIN_FILENO), "Closing STDIN");
+            chk_non_negative(dup2(rw[0],STDIN_FILENO), "Redirecting compressor input to stdin");
+            execlp("gzip","gzip",NULL);
+            _exit(-1);
+    }
+    /* parent */
+    chk_zero(close(rw[0]), "Closing read end of pipe");
+    chk_non_negative(dup2(rw[1],STDOUT_FILENO), "Redirecting output to compressor");
+    
+    rv = write_tar_archive(args);
+
+    chk_zero(close(STDOUT_FILENO), "Closing STDOUT redirected to compressor");
+    chk_non_negative(dup2(stdout2,STDOUT_FILENO), "Restoring uncompressed STDOUT");
+    chk_zero(close(stdout2), "Closing uncompressed STDOUT");
+    chk_zero(close(rw[1]), "Closing write end of pipe in parent");
+    chk_positive(waitpid(gzpid,&status,0), "Waiting on compressor process");
+    if(! ( WIFEXITED(status) && WEXITSTATUS(status)==0 ) )
+            cgit_print_error("Failed to compress archive");
+
+    return rv;
+}
+
 static const struct snapshot_archive_t {
             const char *suffix;
         const char *mimetype;
         write_archive_fn_t write_func;
         }snapshot_archives[] = {
         { ".zip", "application/x-zip", write_zip_archive },
-        { ".tar.gz", "application/x-gzip", write_tar_archive }
+        { ".tar.gz", "application/x-gzip", write_tar_gzip_archive }
 };
 
 void cgit_print_snapshot(struct cacheitem *item, const char *hex, 
                          const char *prefix, const char *filename)
 {
         int fnl = strlen(filename);
         int f;
             for(f=0;f<(sizeof(snapshot_archives)/sizeof(*snapshot_archives));++f) {
                 const struct snapshot_archive_t* sat = &snapshot_archives[f];
                 int sl = strlen(sat->suffix);
                 if(fnl<sl || strcmp(&filename[fnl-sl],sat->suffix))
                         continue;
 
                 struct archiver_args args;
                 struct commit *commit;
                 unsigned char sha1[20];
 
                 if(get_sha1(hex, sha1)) {
                         cgit_print_error(fmt("Bad object id: %s", hex));
                         return;
                 }
                 commit = lookup_commit_reference(sha1);
 
                 if(!commit) {
                         cgit_print_error(fmt("Not a commit reference: %s", hex));
                         return;;
                 }
 
                 memset(&args,0,sizeof(args));
                 args.base = fmt("%s/", prefix);
                 args.tree = commit->tree;
 
                 cgit_print_snapshot_start(sat->mimetype, filename, item);
                 (*sat->write_func)(&args);
                 return;
         }
         cgit_print_error(fmt("Unsupported snapshot format: %s", filename));
 }
 
 void cgit_print_snapshot_links(const char *repo,const char *hex)
 {
             char *filename;
         int f;
             for(f=0;f<(sizeof(snapshot_archives)/sizeof(*snapshot_archives));++f) {
                 const struct snapshot_archive_t* sat = &snapshot_archives[f];
                 filename = fmt("%s-%s%s",repo,hex,sat->suffix);
                 htmlf("<a href='%s'>%s</a><br/>",
                         cgit_pageurl(repo,"snapshot",