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
 38static int write_tar_xz_archive(struct archiver_args *args)
 39{
 40	return write_compressed_tar_archive(args,"xz");
 41}
 42
 43const struct cgit_snapshot_format cgit_snapshot_formats[] = {
 44	{ ".zip", "application/x-zip", write_zip_archive, 0x01 },
 45	{ ".tar.gz", "application/x-gzip", write_tar_gzip_archive, 0x02 },
 46	{ ".tar.bz2", "application/x-bzip2", write_tar_bzip2_archive, 0x04 },
 47	{ ".tar", "application/x-tar", write_tar_archive, 0x08 },
 48	{ ".tar.xz", "application/x-xz", write_tar_xz_archive, 0x10 },
 49	{}
 50};
 51
 52static const struct cgit_snapshot_format *get_format(const char *filename)
 53{
 54	const struct cgit_snapshot_format *fmt;
 55	int fl, sl;
 56
 57	fl = strlen(filename);
 58	for(fmt = cgit_snapshot_formats; fmt->suffix; fmt++) {
 59		sl = strlen(fmt->suffix);
 60		if (sl >= fl)
 61			continue;
 62		if (!strcmp(fmt->suffix, filename + fl - sl))
 63			return fmt;
 64	}
 65	return NULL;
 66}
 67
 68static int make_snapshot(const struct cgit_snapshot_format *format,
 69			 const char *hex, const char *prefix,
 70			 const char *filename)
 71{
 72	struct archiver_args args;
 73	struct commit *commit;
 74	unsigned char sha1[20];
 75
 76	if(get_sha1(hex, sha1)) {
 77		cgit_print_error(fmt("Bad object id: %s", hex));
 78		return 1;
 79	}
 80	commit = lookup_commit_reference(sha1);
 81	if(!commit) {
 82		cgit_print_error(fmt("Not a commit reference: %s", hex));
 83		return 1;
 84	}
 85	memset(&args, 0, sizeof(args));
 86	if (prefix) {
 87		args.base = fmt("%s/", prefix);
 88		args.baselen = strlen(prefix) + 1;
 89	} else {
 90		args.base = "";
 91		args.baselen = 0;
 92	}
 93	args.tree = commit->tree;
 94	args.time = commit->date;
 95	args.compression_level = Z_DEFAULT_COMPRESSION;
 96	ctx.page.mimetype = xstrdup(format->mimetype);
 97	ctx.page.filename = xstrdup(filename);
 98	cgit_print_http_headers(&ctx);
 99	format->write_func(&args);
100	return 0;
101}
102
103/* Try to guess the requested revision from the requested snapshot name.
104 * First the format extension is stripped, e.g. "cgit-0.7.2.tar.gz" become
105 * "cgit-0.7.2". If this is a valid commit object name we've got a winner.
106 * Otherwise, if the snapshot name has a prefix matching the result from
107 * repo_basename(), we strip the basename and any following '-' and '_'
108 * characters ("cgit-0.7.2" -> "0.7.2") and check the resulting name once
109 * more. If this still isn't a valid commit object name, we check if pre-
110 * pending a 'v' to the remaining snapshot name ("0.7.2" -> "v0.7.2") gives
111 * us something valid.
112 */
113static const char *get_ref_from_filename(const char *url, const char *filename,
114					 const struct cgit_snapshot_format *format)
115{
116	const char *reponame;
117	unsigned char sha1[20];
118	char *snapshot;
119
120	snapshot = xstrdup(filename);
121	snapshot[strlen(snapshot) - strlen(format->suffix)] = '\0';
122
123	if (get_sha1(snapshot, sha1) == 0)
124		return snapshot;
125
126	reponame = cgit_repobasename(url);
127	if (prefixcmp(snapshot, reponame) == 0) {
128		snapshot += strlen(reponame);
129		while (snapshot && (*snapshot == '-' || *snapshot == '_'))
130			snapshot++;
131	}
132
133	if (get_sha1(snapshot, sha1) == 0)
134		return snapshot;
135
136	snapshot = fmt("v%s", snapshot);
137	if (get_sha1(snapshot, sha1) == 0)
138		return snapshot;
139
140	return NULL;
141}
142
143void show_error(char *msg)
144{
145	ctx.page.mimetype = "text/html";
146	cgit_print_http_headers(&ctx);
147	cgit_print_docstart(&ctx);
148	cgit_print_pageheader(&ctx);
149	cgit_print_error(msg);
150	cgit_print_docend();
151}
152
153void cgit_print_snapshot(const char *head, const char *hex,
154			 const char *filename, int snapshots, int dwim)
155{
156	const struct cgit_snapshot_format* f;
157	char *prefix = NULL;
158
159	if (!filename) {
160		show_error("No snapshot name specified");
161		return;
162	}
163
164	f = get_format(filename);
165	if (!f) {
166		show_error(xstrdup(fmt("Unsupported snapshot format: %s",
167				       filename)));
168		return;
169	}
170
171	if (!hex && dwim) {
172		hex = get_ref_from_filename(ctx.repo->url, filename, f);
173		if (hex == NULL) {
174			html_status(404, "Not found", 0);
175			return;
176		}
177		prefix = xstrdup(filename);
178		prefix[strlen(filename) - strlen(f->suffix)] = '\0';
179	}
180
181	if (!hex)
182		hex = head;
183
184	if (!prefix)
185		prefix = xstrdup(cgit_repobasename(ctx.repo->url));
186
187	make_snapshot(f, hex, prefix, filename);
188	free(prefix);
189}