cgitsb/ui-snapshot.c
Lars Hjemli 6fddad7251 ui-snapshot: avoid segfault when no filename is specified
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
2009-03-15 08:57:33 +01:00

206 satır
5.5 KiB
C

/* 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"
#include "html.h"
#include "ui-shared.h"
static int write_compressed_tar_archive(struct archiver_args *args,const char *filter)
{
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(filter,filter,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 int write_tar_gzip_archive(struct archiver_args *args)
{
return write_compressed_tar_archive(args,"gzip");
}
static int write_tar_bzip2_archive(struct archiver_args *args)
{
return write_compressed_tar_archive(args,"bzip2");
}
const struct cgit_snapshot_format cgit_snapshot_formats[] = {
{ ".zip", "application/x-zip", write_zip_archive, 0x1 },
{ ".tar.gz", "application/x-gzip", write_tar_gzip_archive, 0x2 },
{ ".tar.bz2", "application/x-bzip2", write_tar_bzip2_archive, 0x4 },
{ ".tar", "application/x-tar", write_tar_archive, 0x8 },
{}
};
static const struct cgit_snapshot_format *get_format(const char *filename)
{
const struct cgit_snapshot_format *fmt;
int fl, sl;
fl = strlen(filename);
for(fmt = cgit_snapshot_formats; fmt->suffix; fmt++) {
sl = strlen(fmt->suffix);
if (sl >= fl)
continue;
if (!strcmp(fmt->suffix, filename + fl - sl))
return fmt;
}
return NULL;
}
static int make_snapshot(const struct cgit_snapshot_format *format,
const char *hex, const char *prefix,
const char *filename)
{
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 1;
}
commit = lookup_commit_reference(sha1);
if(!commit) {
cgit_print_error(fmt("Not a commit reference: %s", hex));
return 1;
}
memset(&args, 0, sizeof(args));
if (prefix) {
args.base = fmt("%s/", prefix);
args.baselen = strlen(prefix) + 1;
} else {
args.base = "";
args.baselen = 0;
}
args.tree = commit->tree;
args.time = commit->date;
ctx.page.mimetype = xstrdup(format->mimetype);
ctx.page.filename = xstrdup(filename);
cgit_print_http_headers(&ctx);
format->write_func(&args);
return 0;
}
/* Try to guess the requested revision from the requested snapshot name.
* First the format extension is stripped, e.g. "cgit-0.7.2.tar.gz" become
* "cgit-0.7.2". If this is a valid commit object name we've got a winner.
* Otherwise, if the snapshot name has a prefix matching the result from
* repo_basename(), we strip the basename and any following '-' and '_'
* characters ("cgit-0.7.2" -> "0.7.2") and check the resulting name once
* more. If this still isn't a valid commit object name, we check if pre-
* pending a 'v' to the remaining snapshot name ("0.7.2" -> "v0.7.2") gives
* us something valid.
*/
static const char *get_ref_from_filename(const char *url, const char *filename,
const struct cgit_snapshot_format *format)
{
const char *reponame;
unsigned char sha1[20];
char *snapshot;
snapshot = xstrdup(filename);
snapshot[strlen(snapshot) - strlen(format->suffix)] = '\0';
fprintf(stderr, "snapshot=%s\n", snapshot);
if (get_sha1(snapshot, sha1) == 0)
return snapshot;
reponame = cgit_repobasename(url);
fprintf(stderr, "reponame=%s\n", reponame);
if (prefixcmp(snapshot, reponame) == 0) {
snapshot += strlen(reponame);
while (snapshot && (*snapshot == '-' || *snapshot == '_'))
snapshot++;
}
if (get_sha1(snapshot, sha1) == 0)
return snapshot;
snapshot = fmt("v%s", snapshot);
if (get_sha1(snapshot, sha1) == 0)
return snapshot;
return NULL;
}
void show_error(char *msg)
{
ctx.page.mimetype = "text/html";
cgit_print_http_headers(&ctx);
cgit_print_docstart(&ctx);
cgit_print_pageheader(&ctx);
cgit_print_error(msg);
cgit_print_docend();
}
void cgit_print_snapshot(const char *head, const char *hex,
const char *filename, int snapshots, int dwim)
{
const struct cgit_snapshot_format* f;
char *prefix = NULL;
if (!filename) {
show_error("No snapshot name specified");
return;
}
f = get_format(filename);
if (!f) {
show_error(xstrdup(fmt("Unsupported snapshot format: %s",
filename)));
return;
}
if (!hex && dwim) {
hex = get_ref_from_filename(ctx.repo->url, filename, f);
if (hex == NULL) {
html_status(404, "Not found", 0);
return;
}
prefix = xstrdup(filename);
prefix[strlen(filename) - strlen(f->suffix)] = '\0';
}
if (!hex)
hex = head;
if (!prefix)
prefix = xstrdup(cgit_repobasename(ctx.repo->url));
make_snapshot(f, hex, prefix, filename);
free(prefix);
}