ui-snapshot.c (view raw)
1/* ui-snapshot.c: generate snapshot of a commit
2 *
3 * Copyright (C) 2006-2014 cgit Development Team <cgit@lists.zx2c4.com>
4 *
5 * Licensed under GNU General Public License v2
6 * (see COPYING for full license text)
7 */
8
9#include "cgit.h"
10#include "ui-snapshot.h"
11#include "html.h"
12#include "ui-shared.h"
13
14static int write_archive_type(const char *format, const char *hex, const char *prefix)
15{
16 struct argv_array argv = ARGV_ARRAY_INIT;
17 const char **nargv;
18 int result;
19 argv_array_push(&argv, "snapshot");
20 argv_array_push(&argv, format);
21 if (prefix) {
22 struct strbuf buf = STRBUF_INIT;
23 strbuf_addstr(&buf, prefix);
24 strbuf_addch(&buf, '/');
25 argv_array_push(&argv, "--prefix");
26 argv_array_push(&argv, buf.buf);
27 strbuf_release(&buf);
28 }
29 argv_array_push(&argv, hex);
30 /*
31 * Now we need to copy the pointers to arguments into a new
32 * structure because write_archive will rearrange its arguments
33 * which may result in duplicated/missing entries causing leaks
34 * or double-frees in argv_array_clear.
35 */
36 nargv = xmalloc(sizeof(char *) * (argv.argc + 1));
37 /* argv_array guarantees a trailing NULL entry. */
38 memcpy(nargv, argv.argv, sizeof(char *) * (argv.argc + 1));
39
40 result = write_archive(argv.argc, nargv, NULL, 1, NULL, 0);
41 argv_array_clear(&argv);
42 free(nargv);
43 return result;
44}
45
46static int write_tar_archive(const char *hex, const char *prefix)
47{
48 return write_archive_type("--format=tar", hex, prefix);
49}
50
51static int write_zip_archive(const char *hex, const char *prefix)
52{
53 return write_archive_type("--format=zip", hex, prefix);
54}
55
56static int write_compressed_tar_archive(const char *hex,
57 const char *prefix,
58 char *filter_argv[])
59{
60 int rv;
61 struct cgit_filter f;
62
63 f.cmd = filter_argv[0];
64 f.argv = filter_argv;
65 cgit_open_filter(&f);
66 rv = write_tar_archive(hex, prefix);
67 cgit_close_filter(&f);
68 return rv;
69}
70
71static int write_tar_gzip_archive(const char *hex, const char *prefix)
72{
73 char *argv[] = { "gzip", "-n", NULL };
74 return write_compressed_tar_archive(hex, prefix, argv);
75}
76
77static int write_tar_bzip2_archive(const char *hex, const char *prefix)
78{
79 char *argv[] = { "bzip2", NULL };
80 return write_compressed_tar_archive(hex, prefix, argv);
81}
82
83static int write_tar_xz_archive(const char *hex, const char *prefix)
84{
85 char *argv[] = { "xz", NULL };
86 return write_compressed_tar_archive(hex, prefix, argv);
87}
88
89const struct cgit_snapshot_format cgit_snapshot_formats[] = {
90 { ".zip", "application/x-zip", write_zip_archive, 0x01 },
91 { ".tar.gz", "application/x-gzip", write_tar_gzip_archive, 0x02 },
92 { ".tar.bz2", "application/x-bzip2", write_tar_bzip2_archive, 0x04 },
93 { ".tar", "application/x-tar", write_tar_archive, 0x08 },
94 { ".tar.xz", "application/x-xz", write_tar_xz_archive, 0x10 },
95 { NULL }
96};
97
98static const struct cgit_snapshot_format *get_format(const char *filename)
99{
100 const struct cgit_snapshot_format *fmt;
101
102 for (fmt = cgit_snapshot_formats; fmt->suffix; fmt++) {
103 if (!suffixcmp(filename, fmt->suffix))
104 return fmt;
105 }
106 return NULL;
107}
108
109static int make_snapshot(const struct cgit_snapshot_format *format,
110 const char *hex, const char *prefix,
111 const char *filename)
112{
113 unsigned char sha1[20];
114
115 if (get_sha1(hex, sha1)) {
116 cgit_print_error("Bad object id: %s", hex);
117 return 1;
118 }
119 if (!lookup_commit_reference(sha1)) {
120 cgit_print_error("Not a commit reference: %s", hex);
121 return 1;
122 }
123 ctx.page.mimetype = xstrdup(format->mimetype);
124 ctx.page.filename = xstrdup(filename);
125 cgit_print_http_headers(&ctx);
126 format->write_func(hex, prefix);
127 return 0;
128}
129
130/* Try to guess the requested revision from the requested snapshot name.
131 * First the format extension is stripped, e.g. "cgit-0.7.2.tar.gz" become
132 * "cgit-0.7.2". If this is a valid commit object name we've got a winner.
133 * Otherwise, if the snapshot name has a prefix matching the result from
134 * repo_basename(), we strip the basename and any following '-' and '_'
135 * characters ("cgit-0.7.2" -> "0.7.2") and check the resulting name once
136 * more. If this still isn't a valid commit object name, we check if pre-
137 * pending a 'v' or a 'V' to the remaining snapshot name ("0.7.2" ->
138 * "v0.7.2") gives us something valid.
139 */
140static const char *get_ref_from_filename(const char *url, const char *filename,
141 const struct cgit_snapshot_format *format)
142{
143 const char *reponame;
144 unsigned char sha1[20];
145 struct strbuf snapshot = STRBUF_INIT;
146 int result = 1;
147
148 strbuf_addstr(&snapshot, filename);
149 strbuf_setlen(&snapshot, snapshot.len - strlen(format->suffix));
150
151 if (get_sha1(snapshot.buf, sha1) == 0)
152 goto out;
153
154 reponame = cgit_repobasename(url);
155 if (prefixcmp(snapshot.buf, reponame) == 0) {
156 const char *new_start = snapshot.buf;
157 new_start += strlen(reponame);
158 while (new_start && (*new_start == '-' || *new_start == '_'))
159 new_start++;
160 strbuf_splice(&snapshot, 0, new_start - snapshot.buf, "", 0);
161 }
162
163 if (get_sha1(snapshot.buf, sha1) == 0)
164 goto out;
165
166 strbuf_insert(&snapshot, 0, "v", 1);
167 if (get_sha1(snapshot.buf, sha1) == 0)
168 goto out;
169
170 strbuf_splice(&snapshot, 0, 1, "V", 1);
171 if (get_sha1(snapshot.buf, sha1) == 0)
172 goto out;
173
174 result = 0;
175 strbuf_release(&snapshot);
176
177out:
178 return result ? strbuf_detach(&snapshot, NULL) : NULL;
179}
180
181__attribute__((format (printf, 1, 2)))
182static void show_error(char *fmt, ...)
183{
184 va_list ap;
185
186 ctx.page.mimetype = "text/html";
187 cgit_print_http_headers(&ctx);
188 cgit_print_docstart(&ctx);
189 cgit_print_pageheader(&ctx);
190 va_start(ap, fmt);
191 cgit_vprint_error(fmt, ap);
192 va_end(ap);
193 cgit_print_docend();
194}
195
196void cgit_print_snapshot(const char *head, const char *hex,
197 const char *filename, int snapshots, int dwim)
198{
199 const struct cgit_snapshot_format* f;
200 char *prefix = NULL;
201
202 if (!filename) {
203 show_error("No snapshot name specified");
204 return;
205 }
206
207 f = get_format(filename);
208 if (!f) {
209 show_error("Unsupported snapshot format: %s", filename);
210 return;
211 }
212
213 if (!hex && dwim) {
214 hex = get_ref_from_filename(ctx.repo->url, filename, f);
215 if (hex == NULL) {
216 html_status(404, "Not found", 0);
217 return;
218 }
219 prefix = xstrdup(filename);
220 prefix[strlen(filename) - strlen(f->suffix)] = '\0';
221 }
222
223 if (!hex)
224 hex = head;
225
226 if (!prefix)
227 prefix = xstrdup(cgit_repobasename(ctx.repo->url));
228
229 make_snapshot(f, hex, prefix, filename);
230 free(prefix);
231}