cgitsb/ui-snapshot.c
John Keeping fb3655df3b use struct strbuf instead of static buffers
Use "struct strbuf" from Git to remove the limit on file path length.

Notes on scan-tree:
This is slightly involved since I decided to pass the strbuf into
add_repo() and modify if whenever a new file name is required, which
should avoid any extra allocations within that function.  The pattern
there is to append the filename, use it and then reset the buffer to its
original length (retaining a trailing '/').

Notes on ui-snapshot:
Since write_archive modifies the argv array passed to it we
copy the argv_array values into a new array of char* and then free the
original argv_array structure and the new array without worrying about
what the values now look like.

Signed-off-by: John Keeping <john@keeping.me.uk>
2013-04-08 16:12:52 +02:00

234 rindas
6.1 KiB
C

/* ui-snapshot.c: generate snapshot of a commit
*
* Copyright (C) 2006 Lars Hjemli
* Copyright (C) 2012 Jason A. Donenfeld <Jason@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_filter f;
f.cmd = filter_argv[0];
f.argv = filter_argv;
cgit_open_filter(&f);
rv = write_tar_archive(hex, prefix);
cgit_close_filter(&f);
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;
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)
{
unsigned char sha1[20];
if (get_sha1(hex, sha1)) {
cgit_print_error("Bad object id: %s", hex);
return 1;
}
if (!lookup_commit_reference(sha1)) {
cgit_print_error("Not a commit reference: %s", hex);
return 1;
}
ctx.page.mimetype = xstrdup(format->mimetype);
ctx.page.filename = xstrdup(filename);
cgit_print_http_headers(&ctx);
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' 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 (prefixcmp(snapshot.buf, reponame) == 0) {
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;
result = 0;
strbuf_release(&snapshot);
out:
return result ? strbuf_detach(&snapshot, NULL) : NULL;
}
__attribute__((format (printf, 1, 2)))
static void show_error(char *fmt, ...)
{
va_list ap;
ctx.page.mimetype = "text/html";
cgit_print_http_headers(&ctx);
cgit_print_docstart(&ctx);
cgit_print_pageheader(&ctx);
va_start(ap, fmt);
cgit_vprint_error(fmt, ap);
va_end(ap);
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("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);
}