cat-file: do not die on --textconv without textconv filters
[git] / builtin / cat-file.c
1 /*
2  * GIT - The information manager from hell
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  */
6 #include "cache.h"
7 #include "exec_cmd.h"
8 #include "tag.h"
9 #include "tree.h"
10 #include "builtin.h"
11 #include "parse-options.h"
12 #include "diff.h"
13 #include "userdiff.h"
14 #include "streaming.h"
15
16 #define BATCH 1
17 #define BATCH_CHECK 2
18
19 static void pprint_tag(const unsigned char *sha1, const char *buf, unsigned long size)
20 {
21         /* the parser in tag.c is useless here. */
22         const char *endp = buf + size;
23         const char *cp = buf;
24
25         while (cp < endp) {
26                 char c = *cp++;
27                 if (c != '\n')
28                         continue;
29                 if (7 <= endp - cp && !memcmp("tagger ", cp, 7)) {
30                         const char *tagger = cp;
31
32                         /* Found the tagger line.  Copy out the contents
33                          * of the buffer so far.
34                          */
35                         write_or_die(1, buf, cp - buf);
36
37                         /*
38                          * Do something intelligent, like pretty-printing
39                          * the date.
40                          */
41                         while (cp < endp) {
42                                 if (*cp++ == '\n') {
43                                         /* tagger to cp is a line
44                                          * that has ident and time.
45                                          */
46                                         const char *sp = tagger;
47                                         char *ep;
48                                         unsigned long date;
49                                         long tz;
50                                         while (sp < cp && *sp != '>')
51                                                 sp++;
52                                         if (sp == cp) {
53                                                 /* give up */
54                                                 write_or_die(1, tagger,
55                                                              cp - tagger);
56                                                 break;
57                                         }
58                                         while (sp < cp &&
59                                                !('0' <= *sp && *sp <= '9'))
60                                                 sp++;
61                                         write_or_die(1, tagger, sp - tagger);
62                                         date = strtoul(sp, &ep, 10);
63                                         tz = strtol(ep, NULL, 10);
64                                         sp = show_date(date, tz, 0);
65                                         write_or_die(1, sp, strlen(sp));
66                                         xwrite(1, "\n", 1);
67                                         break;
68                                 }
69                         }
70                         break;
71                 }
72                 if (cp < endp && *cp == '\n')
73                         /* end of header */
74                         break;
75         }
76         /* At this point, we have copied out the header up to the end of
77          * the tagger line and cp points at one past \n.  It could be the
78          * next header line after the tagger line, or it could be another
79          * \n that marks the end of the headers.  We need to copy out the
80          * remainder as is.
81          */
82         if (cp < endp)
83                 write_or_die(1, cp, endp - cp);
84 }
85
86 static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
87 {
88         unsigned char sha1[20];
89         enum object_type type;
90         char *buf;
91         unsigned long size;
92         struct object_context obj_context;
93
94         if (get_sha1_with_context(obj_name, 0, sha1, &obj_context))
95                 die("Not a valid object name %s", obj_name);
96
97         buf = NULL;
98         switch (opt) {
99         case 't':
100                 type = sha1_object_info(sha1, NULL);
101                 if (type > 0) {
102                         printf("%s\n", typename(type));
103                         return 0;
104                 }
105                 break;
106
107         case 's':
108                 type = sha1_object_info(sha1, &size);
109                 if (type > 0) {
110                         printf("%lu\n", size);
111                         return 0;
112                 }
113                 break;
114
115         case 'e':
116                 return !has_sha1_file(sha1);
117
118         case 'c':
119                 if (!obj_context.path[0])
120                         die("git cat-file --textconv %s: <object> must be <sha1:path>",
121                             obj_name);
122
123                 if (textconv_object(obj_context.path, obj_context.mode, sha1, 1, &buf, &size))
124                         break;
125
126         case 'p':
127                 type = sha1_object_info(sha1, NULL);
128                 if (type < 0)
129                         die("Not a valid object name %s", obj_name);
130
131                 /* custom pretty-print here */
132                 if (type == OBJ_TREE) {
133                         const char *ls_args[3] = { NULL };
134                         ls_args[0] =  "ls-tree";
135                         ls_args[1] =  obj_name;
136                         return cmd_ls_tree(2, ls_args, NULL);
137                 }
138
139                 if (type == OBJ_BLOB)
140                         return stream_blob_to_fd(1, sha1, NULL, 0);
141                 buf = read_sha1_file(sha1, &type, &size);
142                 if (!buf)
143                         die("Cannot read object %s", obj_name);
144                 if (type == OBJ_TAG) {
145                         pprint_tag(sha1, buf, size);
146                         return 0;
147                 }
148
149                 /* otherwise just spit out the data */
150                 break;
151
152         case 0:
153                 if (type_from_string(exp_type) == OBJ_BLOB) {
154                         unsigned char blob_sha1[20];
155                         if (sha1_object_info(sha1, NULL) == OBJ_TAG) {
156                                 enum object_type type;
157                                 unsigned long size;
158                                 char *buffer = read_sha1_file(sha1, &type, &size);
159                                 if (memcmp(buffer, "object ", 7) ||
160                                     get_sha1_hex(buffer + 7, blob_sha1))
161                                         die("%s not a valid tag", sha1_to_hex(sha1));
162                                 free(buffer);
163                         } else
164                                 hashcpy(blob_sha1, sha1);
165
166                         if (sha1_object_info(blob_sha1, NULL) == OBJ_BLOB)
167                                 return stream_blob_to_fd(1, blob_sha1, NULL, 0);
168                         /*
169                          * we attempted to dereference a tag to a blob
170                          * and failed; there may be new dereference
171                          * mechanisms this code is not aware of.
172                          * fall-back to the usual case.
173                          */
174                 }
175                 buf = read_object_with_reference(sha1, exp_type, &size, NULL);
176                 break;
177
178         default:
179                 die("git cat-file: unknown option: %s", exp_type);
180         }
181
182         if (!buf)
183                 die("git cat-file %s: bad file", obj_name);
184
185         write_or_die(1, buf, size);
186         return 0;
187 }
188
189 static int batch_one_object(const char *obj_name, int print_contents)
190 {
191         unsigned char sha1[20];
192         enum object_type type = 0;
193         unsigned long size;
194         void *contents = NULL;
195
196         if (!obj_name)
197            return 1;
198
199         if (get_sha1(obj_name, sha1)) {
200                 printf("%s missing\n", obj_name);
201                 fflush(stdout);
202                 return 0;
203         }
204
205         if (print_contents == BATCH)
206                 contents = read_sha1_file(sha1, &type, &size);
207         else
208                 type = sha1_object_info(sha1, &size);
209
210         if (type <= 0) {
211                 printf("%s missing\n", obj_name);
212                 fflush(stdout);
213                 if (print_contents == BATCH)
214                         free(contents);
215                 return 0;
216         }
217
218         printf("%s %s %lu\n", sha1_to_hex(sha1), typename(type), size);
219         fflush(stdout);
220
221         if (print_contents == BATCH) {
222                 write_or_die(1, contents, size);
223                 printf("\n");
224                 fflush(stdout);
225                 free(contents);
226         }
227
228         return 0;
229 }
230
231 static int batch_objects(int print_contents)
232 {
233         struct strbuf buf = STRBUF_INIT;
234
235         while (strbuf_getline(&buf, stdin, '\n') != EOF) {
236                 int error = batch_one_object(buf.buf, print_contents);
237                 if (error)
238                         return error;
239         }
240
241         return 0;
242 }
243
244 static const char * const cat_file_usage[] = {
245         N_("git cat-file (-t|-s|-e|-p|<type>|--textconv) <object>"),
246         N_("git cat-file (--batch|--batch-check) < <list_of_objects>"),
247         NULL
248 };
249
250 static int git_cat_file_config(const char *var, const char *value, void *cb)
251 {
252         if (userdiff_config(var, value) < 0)
253                 return -1;
254
255         return git_default_config(var, value, cb);
256 }
257
258 int cmd_cat_file(int argc, const char **argv, const char *prefix)
259 {
260         int opt = 0, batch = 0;
261         const char *exp_type = NULL, *obj_name = NULL;
262
263         const struct option options[] = {
264                 OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
265                 OPT_SET_INT('t', NULL, &opt, N_("show object type"), 't'),
266                 OPT_SET_INT('s', NULL, &opt, N_("show object size"), 's'),
267                 OPT_SET_INT('e', NULL, &opt,
268                             N_("exit with zero when there's no error"), 'e'),
269                 OPT_SET_INT('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
270                 OPT_SET_INT(0, "textconv", &opt,
271                             N_("for blob objects, run textconv on object's content"), 'c'),
272                 OPT_SET_INT(0, "batch", &batch,
273                             N_("show info and content of objects fed from the standard input"),
274                             BATCH),
275                 OPT_SET_INT(0, "batch-check", &batch,
276                             N_("show info about objects fed from the standard input"),
277                             BATCH_CHECK),
278                 OPT_END()
279         };
280
281         git_config(git_cat_file_config, NULL);
282
283         if (argc != 3 && argc != 2)
284                 usage_with_options(cat_file_usage, options);
285
286         argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
287
288         if (opt) {
289                 if (argc == 1)
290                         obj_name = argv[0];
291                 else
292                         usage_with_options(cat_file_usage, options);
293         }
294         if (!opt && !batch) {
295                 if (argc == 2) {
296                         exp_type = argv[0];
297                         obj_name = argv[1];
298                 } else
299                         usage_with_options(cat_file_usage, options);
300         }
301         if (batch && (opt || argc)) {
302                 usage_with_options(cat_file_usage, options);
303         }
304
305         if (batch)
306                 return batch_objects(batch);
307
308         return cat_one_file(opt, exp_type, obj_name);
309 }