cgit/ui-snapshot.c
John Keeping 7bd90b8048 filter: add interface layer
Change the existing cgit_{open,close,fprintf}_filter functions to
delegate to filter-specific implementations accessed via function
pointers on the cgit_filter object.

We treat the "exec" filter type slightly specially here by putting its
structure definition in the header file and providing an "init" function
to set up the function pointers.  This is required so that the
ui-snapshot.c code that applies a compression filter can continue to use
the filter interface to do so.

Signed-off-by: John Keeping <john@keeping.me.uk>
2014-01-14 02:00:07 +01:00

231 lines
6.1 KiB
C

/* 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 (!suffixcmp(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("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' 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 (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;
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;
}
__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);
}