cgitsb/ui-snapshot.c
Lars Hjemli ed7ff095ca ui-snapshot: add dwimmery
When downloading a snapshot, the snapshot name will often contain the repo
name combined with a tag. This patch tries to exploit this so that the
correct revision is downloaded even if no specific revision is specified.

PS: this only occurs if neither 'h' nor 'id' is specified in the query-
string.

PPS: this also fixes a bug which occurs when trying to download a filename
with an unsupported suffix: it used to try to print an error message to
the user but failed since it didn't prepare the output properly.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>
2008-10-11 20:09:42 +02:00

189 wiersze
5.4 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-tar", write_tar_gzip_archive, 0x2 },
{ ".tar.bz2", "application/x-tar", 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;
}
char *dwim_filename = NULL;
const char *dwim_refname = NULL;
static int ref_cb(const char *refname, const unsigned char *sha1, int flags,
void *cb_data)
{
const char *r = refname;
while (r && *r) {
fprintf(stderr, " cmp %s with %s:", dwim_filename, r);
if (!strcmp(dwim_filename, r)) {
fprintf(stderr, "MATCH!\n");
dwim_refname = refname;
return 1;
}
fprintf(stderr, "no match\n");
if (isdigit(*r))
break;
r++;
}
return 0;
}
/* Try to guess the requested revision by combining repo name and tag name
* and comparing this to the requested snapshot name. E.g. the requested
* snapshot is "cgit-0.7.2.tar.gz" while repo name is "cgit" and tag name
* is "v0.7.2". First, the reponame is stripped off, leaving "-0.7.2.tar.gz".
* Next, any '-' and '_' characters are stripped, leaving "0.7.2.tar.gz".
* Finally, the requested format suffix is removed and we end up with "0.7.2".
* Then we test each tag against this dwimmed filename, and for each tag
* we even try to remove any leading characters which are non-digits. I.e.
* we first compare with "v0.7.2", then with "0.7.2" and we've got a match.
*/
static const char *get_ref_from_filename(const char *url, const char *filename,
const struct cgit_snapshot_format *fmt)
{
const char *reponame = cgit_repobasename(url);
fprintf(stderr, "reponame=%s, filename=%s\n", reponame, filename);
if (prefixcmp(filename, reponame))
return NULL;
filename += strlen(reponame);
while (filename && (*filename == '-' || *filename == '_'))
filename++;
dwim_filename = xstrdup(filename);
dwim_filename[strlen(filename) - strlen(fmt->suffix)] = '\0';
for_each_tag_ref(ref_cb, NULL);
return dwim_refname;
}
void cgit_print_snapshot(const char *head, const char *hex, const char *prefix,
const char *filename, int snapshots, int dwim)
{
const struct cgit_snapshot_format* f;
f = get_format(filename);
if (!f) {
ctx.page.mimetype = "text/html";
cgit_print_http_headers(&ctx);
cgit_print_docstart(&ctx);
cgit_print_pageheader(&ctx);
cgit_print_error(fmt("Unsupported snapshot format: %s", filename));
cgit_print_docend();
return;
}
if (!hex && dwim)
hex = get_ref_from_filename(ctx.repo->url, filename, f);
if (!hex)
hex = head;
make_snapshot(f, hex, prefix, filename);
}