ui-snapshot.c (view raw)
1/* ui-snapshot.c: generate snapshot of a commit
2 *
3 * Copyright (C) 2006 Lars Hjemli
4 * Copyright (C) 2012 Jason A. Donenfeld <Jason@zx2c4.com>
5 *
6 * Licensed under GNU General Public License v2
7 * (see COPYING for full license text)
8 */
9
10#include "cgit.h"
11#include "ui-snapshot.h"
12#include "html.h"
13#include "ui-shared.h"
14
15static int write_archive_type(const char *format, const char *hex, const char *prefix)
16{
17 struct argv_array argv = ARGV_ARRAY_INIT;
18 const char **nargv;
19 int result;
20 argv_array_push(&argv, "snapshot");
21 argv_array_push(&argv, format);
22 if (prefix) {
23 struct strbuf buf = STRBUF_INIT;
24 strbuf_addstr(&buf, prefix);
25 strbuf_addch(&buf, '/');
26 argv_array_push(&argv, "--prefix");
27 argv_array_push(&argv, buf.buf);
28 strbuf_release(&buf);
29 }
30 argv_array_push(&argv, hex);
31 /*
32 * Now we need to copy the pointers to arguments into a new
33 * structure because write_archive will rearrange its arguments
34 * which may result in duplicated/missing entries causing leaks
35 * or double-frees in argv_array_clear.
36 */
37 nargv = xmalloc(sizeof(char *) * (argv.argc + 1));
38 /* argv_array guarantees a trailing NULL entry. */
39 memcpy(nargv, argv.argv, sizeof(char *) * (argv.argc + 1));
40
41 result = write_archive(argv.argc, nargv, NULL, 1, NULL, 0);
42 argv_array_clear(&argv);
43 free(nargv);
44 return result;
45}
46
47static int write_tar_archive(const char *hex, const char *prefix)
48{
49 return write_archive_type("--format=tar", hex, prefix);
50}
51
52static int write_zip_archive(const char *hex, const char *prefix)
53{
54 return write_archive_type("--format=zip", hex, prefix);
55}
56
57static int write_compressed_tar_archive(const char *hex,
58 const char *prefix,
59 char *filter_argv[])
60{
61 int rv;
62 struct cgit_filter f;
63
64 f.cmd = filter_argv[0];
65 f.argv = filter_argv;
66 cgit_open_filter(&f);
67 rv = write_tar_archive(hex, prefix);
68 cgit_close_filter(&f);
69 return rv;
70}
71
72static int write_tar_gzip_archive(const char *hex, const char *prefix)
73{
74 char *argv[] = { "gzip", "-n", NULL };
75 return write_compressed_tar_archive(hex, prefix, argv);
76}
77
78static int write_tar_bzip2_archive(const char *hex, const char *prefix)
79{
80 char *argv[] = { "bzip2", NULL };
81 return write_compressed_tar_archive(hex, prefix, argv);
82}
83
84static int write_tar_xz_archive(const char *hex, const char *prefix)
85{
86 char *argv[] = { "xz", NULL };
87 return write_compressed_tar_archive(hex, prefix, argv);
88}
89
90const struct cgit_snapshot_format cgit_snapshot_formats[] = {
91 { ".zip", "application/x-zip", write_zip_archive, 0x01 },
92 { ".tar.gz", "application/x-gzip", write_tar_gzip_archive, 0x02 },
93 { ".tar.bz2", "application/x-bzip2", write_tar_bzip2_archive, 0x04 },
94 { ".tar", "application/x-tar", write_tar_archive, 0x08 },
95 { ".tar.xz", "application/x-xz", write_tar_xz_archive, 0x10 },
96 { NULL }
97};
98
99static const struct cgit_snapshot_format *get_format(const char *filename)
100{
101 const struct cgit_snapshot_format *fmt;
102 int fl, sl;
103
104 fl = strlen(filename);
105 for (fmt = cgit_snapshot_formats; fmt->suffix; fmt++) {
106 sl = strlen(fmt->suffix);
107 if (sl >= fl)
108 continue;
109 if (!strcmp(fmt->suffix, filename + fl - sl))
110 return fmt;
111 }
112 return NULL;
113}
114
115static int make_snapshot(const struct cgit_snapshot_format *format,
116 const char *hex, const char *prefix,
117 const char *filename)
118{
119 unsigned char sha1[20];
120
121 if (get_sha1(hex, sha1)) {
122 cgit_print_error("Bad object id: %s", hex);
123 return 1;
124 }
125 if (!lookup_commit_reference(sha1)) {
126 cgit_print_error("Not a commit reference: %s", hex);
127 return 1;
128 }
129 ctx.page.mimetype = xstrdup(format->mimetype);
130 ctx.page.filename = xstrdup(filename);
131 cgit_print_http_headers(&ctx);
132 format->write_func(hex, prefix);
133 return 0;
134}
135
136/* Try to guess the requested revision from the requested snapshot name.
137 * First the format extension is stripped, e.g. "cgit-0.7.2.tar.gz" become
138 * "cgit-0.7.2". If this is a valid commit object name we've got a winner.
139 * Otherwise, if the snapshot name has a prefix matching the result from
140 * repo_basename(), we strip the basename and any following '-' and '_'
141 * characters ("cgit-0.7.2" -> "0.7.2") and check the resulting name once
142 * more. If this still isn't a valid commit object name, we check if pre-
143 * pending a 'v' to the remaining snapshot name ("0.7.2" -> "v0.7.2") gives
144 * us something valid.
145 */
146static const char *get_ref_from_filename(const char *url, const char *filename,
147 const struct cgit_snapshot_format *format)
148{
149 const char *reponame;
150 unsigned char sha1[20];
151 struct strbuf snapshot = STRBUF_INIT;
152 int result = 1;
153
154 strbuf_addstr(&snapshot, filename);
155 strbuf_setlen(&snapshot, snapshot.len - strlen(format->suffix));
156
157 if (get_sha1(snapshot.buf, sha1) == 0)
158 goto out;
159
160 reponame = cgit_repobasename(url);
161 if (prefixcmp(snapshot.buf, reponame) == 0) {
162 const char *new_start = snapshot.buf;
163 new_start += strlen(reponame);
164 while (new_start && (*new_start == '-' || *new_start == '_'))
165 new_start++;
166 strbuf_splice(&snapshot, 0, new_start - snapshot.buf, "", 0);
167 }
168
169 if (get_sha1(snapshot.buf, sha1) == 0)
170 goto out;
171
172 strbuf_insert(&snapshot, 0, "v", 1);
173 if (get_sha1(snapshot.buf, sha1) == 0)
174 goto out;
175
176 result = 0;
177 strbuf_release(&snapshot);
178
179out:
180 return result ? strbuf_detach(&snapshot, NULL) : NULL;
181}
182
183__attribute__((format (printf, 1, 2)))
184static void show_error(char *fmt, ...)
185{
186 va_list ap;
187
188 ctx.page.mimetype = "text/html";
189 cgit_print_http_headers(&ctx);
190 cgit_print_docstart(&ctx);
191 cgit_print_pageheader(&ctx);
192 va_start(ap, fmt);
193 cgit_vprint_error(fmt, ap);
194 va_end(ap);
195 cgit_print_docend();
196}
197
198void cgit_print_snapshot(const char *head, const char *hex,
199 const char *filename, int snapshots, int dwim)
200{
201 const struct cgit_snapshot_format* f;
202 char *prefix = NULL;
203
204 if (!filename) {
205 show_error("No snapshot name specified");
206 return;
207 }
208
209 f = get_format(filename);
210 if (!f) {
211 show_error("Unsupported snapshot format: %s", filename);
212 return;
213 }
214
215 if (!hex && dwim) {
216 hex = get_ref_from_filename(ctx.repo->url, filename, f);
217 if (hex == NULL) {
218 html_status(404, "Not found", 0);
219 return;
220 }
221 prefix = xstrdup(filename);
222 prefix[strlen(filename) - strlen(f->suffix)] = '\0';
223 }
224
225 if (!hex)
226 hex = head;
227
228 if (!prefix)
229 prefix = xstrdup(cgit_repobasename(ctx.repo->url));
230
231 make_snapshot(f, hex, prefix, filename);
232 free(prefix);
233}