archive.c

   1 #include "cache.h"
   2 #include "commit.h"
   3 #include "tree-walk.h"
   4 #include "attr.h"
   5 #include "archive.h"
   6
   7 static const char archive_usage[] = \
   8 "git archive --format=<fmt> [--prefix=<prefix>/] [--verbose] [<extra>] <tree-ish> [path...]";
   9
  10 #define USES_ZLIB_COMPRESSION 1
  11
  12 const struct archiver {
  13         const char *name;
  14         write_archive_fn_t write_archive;
  15         unsigned int flags;
  16 } archivers[] = {
  17         { "tar", write_tar_archive },
  18         { "zip", write_zip_archive, USES_ZLIB_COMPRESSION },
  19 };
  20
  21 static void format_subst(const struct commit *commit,
  22                          const char *src, size_t len,
  23                          struct strbuf *buf)
  24 {
  25         char *to_free = NULL;
  26         struct strbuf fmt;
  27
  28         if (src == buf->buf)
  29                 to_free = strbuf_detach(buf, NULL);
  30         strbuf_init(&fmt, 0);
  31         for (;;) {
  32                 const char *b, *c;
  33
  34                 b = memmem(src, len, "$Format:", 8);
  35                 if (!b)
  36                         break;
  37                 c = memchr(b + 8, '$', (src + len) - b - 8);
  38                 if (!c)
  39                         break;
  40
  41                 strbuf_reset(&fmt);
  42                 strbuf_add(&fmt, b + 8, c - b - 8);
  43
  44                 strbuf_add(buf, src, b - src);
  45                 format_commit_message(commit, fmt.buf, buf);
  46                 len -= c + 1 - src;
  47                 src  = c + 1;
  48         }
  49         strbuf_add(buf, src, len);
  50         strbuf_release(&fmt);
  51         free(to_free);
  52 }
  53
  54 static void *sha1_file_to_archive(const char *path, const unsigned char *sha1,
  55                 unsigned int mode, enum object_type *type,
  56                 unsigned long *sizep, const struct commit *commit)
  57 {
  58         void *buffer;
  59
  60         buffer = read_sha1_file(sha1, type, sizep);
  61         if (buffer && S_ISREG(mode)) {
  62                 struct strbuf buf;
  63                 size_t size = 0;
  64
  65                 strbuf_init(&buf, 0);
  66                 strbuf_attach(&buf, buffer, *sizep, *sizep + 1);
  67                 convert_to_working_tree(path, buf.buf, buf.len, &buf);
  68                 if (commit)
  69                         format_subst(commit, buf.buf, buf.len, &buf);
  70                 buffer = strbuf_detach(&buf, &size);
  71                 *sizep = size;
  72         }
  73
  74         return buffer;
  75 }
  76
  77 static void setup_archive_check(struct git_attr_check *check)
  78 {
  79         static struct git_attr *attr_export_ignore;
  80         static struct git_attr *attr_export_subst;
  81
  82         if (!attr_export_ignore) {
  83                 attr_export_ignore = git_attr("export-ignore", 13);
  84                 attr_export_subst = git_attr("export-subst", 12);
  85         }
  86         check[0].attr = attr_export_ignore;
  87         check[1].attr = attr_export_subst;
  88 }
  89
  90 struct archiver_context {
  91         struct archiver_args *args;
  92         write_archive_entry_fn_t write_entry;
  93 };
  94
  95 static int write_archive_entry(const unsigned char *sha1, const char *base,
  96                 int baselen, const char *filename, unsigned mode, int stage,
  97                 void *context)
  98 {
  99         static struct strbuf path = STRBUF_INIT;
 100         struct archiver_context *c = context;
 101         struct archiver_args *args = c->args;
 102         write_archive_entry_fn_t write_entry = c->write_entry;
 103         struct git_attr_check check[2];
 104         const char *path_without_prefix;
 105         int convert = 0;
 106         int err;
 107         enum object_type type;
 108         unsigned long size;
 109         void *buffer;
 110
 111         strbuf_reset(&path);
 112         strbuf_grow(&path, PATH_MAX);
 113         strbuf_add(&path, base, baselen);
 114         strbuf_addstr(&path, filename);
 115         path_without_prefix = path.buf + args->baselen;
 116
 117         setup_archive_check(check);
 118         if (!git_checkattr(path_without_prefix, ARRAY_SIZE(check), check)) {
 119                 if (ATTR_TRUE(check[0].value))
 120                         return 0;
 121                 convert = ATTR_TRUE(check[1].value);
 122         }
 123
 124         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 125                 strbuf_addch(&path, '/');
 126                 if (args->verbose)
 127                         fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
 128                 err = write_entry(args, sha1, path.buf, path.len, mode, NULL, 0);
 129                 if (err)
 130                         return err;
 131                 return READ_TREE_RECURSIVE;
 132         }
 133
 134         buffer = sha1_file_to_archive(path_without_prefix, sha1, mode,
 135                         &type, &size, convert ? args->commit : NULL);
 136         if (!buffer)
 137                 return error("cannot read %s", sha1_to_hex(sha1));
 138         if (args->verbose)
 139                 fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
 140         err = write_entry(args, sha1, path.buf, path.len, mode, buffer, size);
 141         free(buffer);
 142         return err;
 143 }
 144
 145 int write_archive_entries(struct archiver_args *args,
 146                 write_archive_entry_fn_t write_entry)
 147 {
 148         struct archiver_context context;
 149         int err;
 150
 151         if (args->baselen > 0 && args->base[args->baselen - 1] == '/') {
 152                 size_t len = args->baselen;
 153
 154                 while (len > 1 && args->base[len - 2] == '/')
 155                         len--;
 156                 if (args->verbose)
 157                         fprintf(stderr, "%.*s\n", (int)len, args->base);
 158                 err = write_entry(args, args->tree->object.sha1, args->base,
 159                                 len, 040777, NULL, 0);
 160                 if (err)
 161                         return err;
 162         }
 163
 164         context.args = args;
 165         context.write_entry = write_entry;
 166
 167         err =  read_tree_recursive(args->tree, args->base, args->baselen, 0,
 168                         args->pathspec, write_archive_entry, &context);
 169         if (err == READ_TREE_RECURSIVE)
 170                 err = 0;
 171         return err;
 172 }
 173
 174 static const struct archiver *lookup_archiver(const char *name)
 175 {
 176         int i;
 177
 178         for (i = 0; i < ARRAY_SIZE(archivers); i++) {
 179                 if (!strcmp(name, archivers[i].name))
 180                         return &archivers[i];
 181         }
 182         return NULL;
 183 }
 184
 185 static void parse_pathspec_arg(const char **pathspec,
 186                 struct archiver_args *ar_args)
 187 {
 188         ar_args->pathspec = get_pathspec(ar_args->base, pathspec);
 189 }
 190
 191 static void parse_treeish_arg(const char **argv,
 192                 struct archiver_args *ar_args, const char *prefix)
 193 {
 194         const char *name = argv[0];
 195         const unsigned char *commit_sha1;
 196         time_t archive_time;
 197         struct tree *tree;
 198         const struct commit *commit;
 199         unsigned char sha1[20];
 200
 201         if (get_sha1(name, sha1))
 202                 die("Not a valid object name");
 203
 204         commit = lookup_commit_reference_gently(sha1, 1);
 205         if (commit) {
 206                 commit_sha1 = commit->object.sha1;
 207                 archive_time = commit->date;
 208         } else {
 209                 commit_sha1 = NULL;
 210                 archive_time = time(NULL);
 211         }
 212
 213         tree = parse_tree_indirect(sha1);
 214         if (tree == NULL)
 215                 die("not a tree object");
 216
 217         if (prefix) {
 218                 unsigned char tree_sha1[20];
 219                 unsigned int mode;
 220                 int err;
 221
 222                 err = get_tree_entry(tree->object.sha1, prefix,
 223                                      tree_sha1, &mode);
 224                 if (err || !S_ISDIR(mode))
 225                         die("current working directory is untracked");
 226
 227                 tree = parse_tree_indirect(tree_sha1);
 228         }
 229         ar_args->tree = tree;
 230         ar_args->commit_sha1 = commit_sha1;
 231         ar_args->commit = commit;
 232         ar_args->time = archive_time;
 233 }
 234
 235 static int parse_archive_args(int argc, const char **argv,
 236                 const struct archiver **ar, struct archiver_args *args)
 237 {
 238         const char *format = "tar";
 239         const char *base = "";
 240         int compression_level = -1;
 241         int verbose = 0;
 242         int i;
 243
 244         for (i = 1; i < argc; i++) {
 245                 const char *arg = argv[i];
 246
 247                 if (!strcmp(arg, "--list") || !strcmp(arg, "-l")) {
 248                         for (i = 0; i < ARRAY_SIZE(archivers); i++)
 249                                 printf("%s\n", archivers[i].name);
 250                         exit(0);
 251                 }
 252                 if (!strcmp(arg, "--verbose") || !strcmp(arg, "-v")) {
 253                         verbose = 1;
 254                         continue;
 255                 }
 256                 if (!prefixcmp(arg, "--format=")) {
 257                         format = arg + 9;
 258                         continue;
 259                 }
 260                 if (!prefixcmp(arg, "--prefix=")) {
 261                         base = arg + 9;
 262                         continue;
 263                 }
 264                 if (!strcmp(arg, "--")) {
 265                         i++;
 266                         break;
 267                 }
 268                 if (arg[0] == '-' && isdigit(arg[1]) && arg[2] == '\0') {
 269                         compression_level = arg[1] - '0';
 270                         continue;
 271                 }
 272                 if (arg[0] == '-')
 273                         die("Unknown argument: %s", arg);
 274                 break;
 275         }
 276
 277         /* We need at least one parameter -- tree-ish */
 278         if (argc - 1 < i)
 279                 usage(archive_usage);
 280         *ar = lookup_archiver(format);
 281         if (!*ar)
 282                 die("Unknown archive format '%s'", format);
 283
 284         args->compression_level = Z_DEFAULT_COMPRESSION;
 285         if (compression_level != -1) {
 286                 if ((*ar)->flags & USES_ZLIB_COMPRESSION)
 287                         args->compression_level = compression_level;
 288                 else {
 289                         die("Argument not supported for format '%s': -%d",
 290                                         format, compression_level);
 291                 }
 292         }
 293         args->verbose = verbose;
 294         args->base = base;
 295         args->baselen = strlen(base);
 296
 297         return i;
 298 }
 299
 300 int write_archive(int argc, const char **argv, const char *prefix,
 301                 int setup_prefix)
 302 {
 303         const struct archiver *ar = NULL;
 304         struct archiver_args args;
 305         int tree_idx;
 306
 307         tree_idx = parse_archive_args(argc, argv, &ar, &args);
 308         if (setup_prefix && prefix == NULL)
 309                 prefix = setup_git_directory();
 310
 311         argv += tree_idx;
 312         parse_treeish_arg(argv, &args, prefix);
 313         parse_pathspec_arg(argv + 1, &args);
 314
 315         return ar->write_archive(&args);
 316 }