/* ui-snapshot.c: generate snapshot of a commit
*
* Copyright (C) 2006-2014 cgit Development Team <cgit@lists.zx2c4.com>
*
* Licensed under GNU General Public License v2
* (see COPYING for full license text)
*/
#include "cgit.h"
#include "ui-snapshot.h"
#include "html.h"
#include "ui-shared.h"
static int write_archive_type(const char *format, const char *hex, const char *prefix)
{
struct argv_array argv = ARGV_ARRAY_INIT;
const char **nargv;
int result;
argv_array_push(&argv, "snapshot");
argv_array_push(&argv, format);
if (prefix) {
struct strbuf buf = STRBUF_INIT;
strbuf_addstr(&buf, prefix);
strbuf_addch(&buf, '/');
argv_array_push(&argv, "--prefix");
argv_array_push(&argv, buf.buf);
strbuf_release(&buf);
}
argv_array_push(&argv, hex);
/*
* Now we need to copy the pointers to arguments into a new
* structure because write_archive will rearrange its arguments
* which may result in duplicated/missing entries causing leaks
* or double-frees in argv_array_clear.
*/
nargv = xmalloc(sizeof(char *) * (argv.argc + 1));
/* argv_array guarantees a trailing NULL entry. */
memcpy(nargv, argv.argv, sizeof(char *) * (argv.argc + 1));
result = write_archive(argv.argc, nargv, NULL, 1, NULL, 0);
argv_array_clear(&argv);
free(nargv);
return result;
}
static int write_tar_archive(const char *hex, const char *prefix)
{
return write_archive_type("--format=tar", hex, prefix);
}
static int write_zip_archive(const char *hex, const char *prefix)
{
return write_archive_type("--format=zip", hex, prefix);
}
static int write_compressed_tar_archive(const char *hex,
const char *prefix,
char *filter_argv[])
{
int rv;
struct cgit_exec_filter f;
cgit_exec_filter_init(&f, filter_argv[0], filter_argv);
cgit_open_filter(&f.base);
rv = write_tar_archive(hex, prefix);
cgit_close_filter(&f.base);
return rv;
}
static int write_tar_gzip_archive(const char *hex, const char *prefix)
{
char *argv[] = { "gzip", "-n", NULL };
return write_compressed_tar_archive(hex, prefix, argv);
}
static int write_tar_bzip2_archive(const char *hex, const char *prefix)
{
char *argv[] = { "bzip2", NULL };
return write_compressed_tar_archive(hex, prefix, argv);
}
static int write_tar_xz_archive(const char *hex, const char *prefix)
{
char *argv[] = { "xz", NULL };
return write_compressed_tar_archive(hex, prefix, argv);
}
const struct cgit_snapshot_format cgit_snapshot_formats[] = {
{ ".zip", "application/x-zip", write_zip_archive, 0x01 },
{ ".tar.gz", "application/x-gzip", write_tar_gzip_archive, 0x02 },
{ ".tar.bz2", "application/x-bzip2", write_tar_bzip2_archive, 0x04 },
{ ".tar", "application/x-tar", write_tar_archive, 0x08 },
{ ".tar.xz", "application/x-xz", write_tar_xz_archive, 0x10 },
{ NULL }
};
static const struct cgit_snapshot_format *get_format(const char *filename)
{
const struct cgit_snapshot_format *fmt;
for (fmt = cgit_snapshot_formats; fmt->suffix; fmt++) {
if (ends_with(filename, fmt->suffix))
return fmt;
}
return NULL;
}
static int make_snapshot(const struct cgit_snapshot_format *format,
const char *hex, const char *prefix,
const char *filename)
{
unsigned char sha1[20];
if (get_sha1(hex, sha1)) {
cgit_print_error_page(404, "Not found",
"Bad object id: %s", hex);
return 1;
}
if (!lookup_commit_reference(sha1)) {
cgit_print_error_page(400, "Bad request",
"Not a commit reference: %s", hex);
return 1;
}
ctx.page.etag = sha1_to_hex(sha1);
ctx.page.mimetype = xstrdup(format->mimetype);
ctx.page.filename = xstrdup(filename);
cgit_print_http_headers();
format->write_func(hex, prefix);
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' or 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];
struct strbuf snapshot = STRBUF_INIT;
int result = 1;
strbuf_addstr(&snapshot, filename);
strbuf_setlen(&snapshot, snapshot.len - strlen(format->suffix));
if (get_sha1(snapshot.buf, sha1) == 0)
goto out;
reponame = cgit_repobasename(url);
if (starts_with(snapshot.buf, reponame)) {
const char *new_start = snapshot.buf;
new_start += strlen(reponame);
while (new_start && (*new_start == '-' || *new_start == '_'))
new_start++;
strbuf_splice(&snapshot, 0, new_start - snapshot.buf, "", 0);
}
if (get_sha1(snapshot.buf, sha1) == 0)
goto out;
strbuf_insert(&snapshot, 0, "v", 1);
if (get_sha1(snapshot.buf, sha1) == 0)
goto out;
strbuf_splice(&snapshot, 0, 1, "V", 1);
if (get_sha1(snapshot.buf, sha1) == 0)
goto out;
result = 0;
strbuf_release(&snapshot);
out:
return result ? strbuf_detach(&snapshot, NULL) : NULL;
}
void cgit_print_snapshot(const char *head, const char *hex,
const char *filename, int dwim)
{
const struct cgit_snapshot_format* f;
char *prefix = NULL;
if (!filename) {
cgit_print_error_page(400, "Bad request",
"No snapshot name specified");
return;
}
f = get_format(filename);
if (!f) {
cgit_print_error_page(400, "Bad request",
"Unsupported snapshot format: %s", filename);
return;
}
if (!hex && dwim) {
hex = get_ref_from_filename(ctx.repo->url, filename, f);
if (hex == NULL) {
cgit_print_error_page(404, "Not found", "Not found");
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);
}
