1/* ui-snapshot.c: generate snapshot of a commit
  2 *
  3 * Copyright (C) 2006 Lars Hjemli
  4 *
  5 * Licensed under GNU General Public License v2
  6 *   (see COPYING for full license text)
  7 */
  8
  9#include "cgit.h"
 10#include "html.h"
 11#include "ui-shared.h"
 12
 13static int write_compressed_tar_archive(struct archiver_args *args,const char *filter)
 14{
 15	int rv;
 16	struct cgit_filter f;
 17
 18	f.cmd = xstrdup(filter);
 19	f.argv = malloc(2 * sizeof(char *));
 20	f.argv[0] = f.cmd;
 21	f.argv[1] = NULL;
 22	cgit_open_filter(&f);
 23	rv = write_tar_archive(args);
 24	cgit_close_filter(&f);
 25	return rv;
 26}
 27
 28static int write_tar_gzip_archive(struct archiver_args *args)
 29{
 30	return write_compressed_tar_archive(args,"gzip");
 31}
 32
 33static int write_tar_bzip2_archive(struct archiver_args *args)
 34{
 35	return write_compressed_tar_archive(args,"bzip2");
 36}
 37
 38const struct cgit_snapshot_format cgit_snapshot_formats[] = {
 39	{ ".zip", "application/x-zip", write_zip_archive, 0x1 },
 40	{ ".tar.gz", "application/x-gzip", write_tar_gzip_archive, 0x2 },
 41	{ ".tar.bz2", "application/x-bzip2", write_tar_bzip2_archive, 0x4 },
 42	{ ".tar", "application/x-tar", write_tar_archive, 0x8 },
 43	{}
 44};
 45
 46static const struct cgit_snapshot_format *get_format(const char *filename)
 47{
 48	const struct cgit_snapshot_format *fmt;
 49	int fl, sl;
 50
 51	fl = strlen(filename);
 52	for(fmt = cgit_snapshot_formats; fmt->suffix; fmt++) {
 53		sl = strlen(fmt->suffix);
 54		if (sl >= fl)
 55			continue;
 56		if (!strcmp(fmt->suffix, filename + fl - sl))
 57			return fmt;
 58	}
 59	return NULL;
 60}
 61
 62static int make_snapshot(const struct cgit_snapshot_format *format,
 63			 const char *hex, const char *prefix,
 64			 const char *filename)
 65{
 66	struct archiver_args args;
 67	struct commit *commit;
 68	unsigned char sha1[20];
 69
 70	if(get_sha1(hex, sha1)) {
 71		cgit_print_error(fmt("Bad object id: %s", hex));
 72		return 1;
 73	}
 74	commit = lookup_commit_reference(sha1);
 75	if(!commit) {
 76		cgit_print_error(fmt("Not a commit reference: %s", hex));
 77		return 1;
 78	}
 79	memset(&args, 0, sizeof(args));
 80	if (prefix) {
 81		args.base = fmt("%s/", prefix);
 82		args.baselen = strlen(prefix) + 1;
 83	} else {
 84		args.base = "";
 85		args.baselen = 0;
 86	}
 87	args.tree = commit->tree;
 88	args.time = commit->date;
 89	ctx.page.mimetype = xstrdup(format->mimetype);
 90	ctx.page.filename = xstrdup(filename);
 91	cgit_print_http_headers(&ctx);
 92	format->write_func(&args);
 93	return 0;
 94}
 95
 96/* Try to guess the requested revision from the requested snapshot name.
 97 * First the format extension is stripped, e.g. "cgit-0.7.2.tar.gz" become
 98 * "cgit-0.7.2". If this is a valid commit object name we've got a winner.
 99 * Otherwise, if the snapshot name has a prefix matching the result from
100 * repo_basename(), we strip the basename and any following '-' and '_'
101 * characters ("cgit-0.7.2" -> "0.7.2") and check the resulting name once
102 * more. If this still isn't a valid commit object name, we check if pre-
103 * pending a 'v' to the remaining snapshot name ("0.7.2" -> "v0.7.2") gives
104 * us something valid.
105 */
106static const char *get_ref_from_filename(const char *url, const char *filename,
107					 const struct cgit_snapshot_format *format)
108{
109	const char *reponame;
110	unsigned char sha1[20];
111	char *snapshot;
112
113	snapshot = xstrdup(filename);
114	snapshot[strlen(snapshot) - strlen(format->suffix)] = '\0';
115	fprintf(stderr, "snapshot=%s\n", snapshot);
116
117	if (get_sha1(snapshot, sha1) == 0)
118		return snapshot;
119
120	reponame = cgit_repobasename(url);
121	fprintf(stderr, "reponame=%s\n", reponame);
122	if (prefixcmp(snapshot, reponame) == 0) {
123		snapshot += strlen(reponame);
124		while (snapshot && (*snapshot == '-' || *snapshot == '_'))
125			snapshot++;
126	}
127
128	if (get_sha1(snapshot, sha1) == 0)
129		return snapshot;
130
131	snapshot = fmt("v%s", snapshot);
132	if (get_sha1(snapshot, sha1) == 0)
133		return snapshot;
134
135	return NULL;
136}
137
138void show_error(char *msg)
139{
140	ctx.page.mimetype = "text/html";
141	cgit_print_http_headers(&ctx);
142	cgit_print_docstart(&ctx);
143	cgit_print_pageheader(&ctx);
144	cgit_print_error(msg);
145	cgit_print_docend();
146}
147
148void cgit_print_snapshot(const char *head, const char *hex,
149			 const char *filename, int snapshots, int dwim)
150{
151	const struct cgit_snapshot_format* f;
152	char *prefix = NULL;
153
154	if (!filename) {
155		show_error("No snapshot name specified");
156		return;
157	}
158
159	f = get_format(filename);
160	if (!f) {
161		show_error(xstrdup(fmt("Unsupported snapshot format: %s",
162				       filename)));
163		return;
164	}
165
166	if (!hex && dwim) {
167		hex = get_ref_from_filename(ctx.repo->url, filename, f);
168		if (hex == NULL) {
169			html_status(404, "Not found", 0);
170			return;
171		}
172		prefix = xstrdup(filename);
173		prefix[strlen(filename) - strlen(f->suffix)] = '\0';
174	}
175
176	if (!hex)
177		hex = head;
178
179	if (!prefix)
180		prefix = xstrdup(cgit_repobasename(ctx.repo->url));
181
182	make_snapshot(f, hex, prefix, filename);
183	free(prefix);
184}