Fix some documentation typoes
[git.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
12 static void flush_buffer(const char *buf, unsigned long size)
13 {
14         while (size > 0) {
15                 long ret = xwrite(1, buf, size);
16                 if (ret < 0) {
17                         /* Ignore epipe */
18                         if (errno == EPIPE)
19                                 break;
20                         die("git-cat-file: %s", strerror(errno));
21                 } else if (!ret) {
22                         die("git-cat-file: disk full?");
23                 }
24                 size -= ret;
25                 buf += ret;
26         }
27 }
28
29 static int pprint_tag(const unsigned char *sha1, const char *buf, unsigned long size)
30 {
31         /* the parser in tag.c is useless here. */
32         const char *endp = buf + size;
33         const char *cp = buf;
34
35         while (cp < endp) {
36                 char c = *cp++;
37                 if (c != '\n')
38                         continue;
39                 if (7 <= endp - cp && !memcmp("tagger ", cp, 7)) {
40                         const char *tagger = cp;
41
42                         /* Found the tagger line.  Copy out the contents
43                          * of the buffer so far.
44                          */
45                         flush_buffer(buf, cp - buf);
46
47                         /*
48                          * Do something intelligent, like pretty-printing
49                          * the date.
50                          */
51                         while (cp < endp) {
52                                 if (*cp++ == '\n') {
53                                         /* tagger to cp is a line
54                                          * that has ident and time.
55                                          */
56                                         const char *sp = tagger;
57                                         char *ep;
58                                         unsigned long date;
59                                         long tz;
60                                         while (sp < cp && *sp != '>')
61                                                 sp++;
62                                         if (sp == cp) {
63                                                 /* give up */
64                                                 flush_buffer(tagger,
65                                                              cp - tagger);
66                                                 break;
67                                         }
68                                         while (sp < cp &&
69                                                !('0' <= *sp && *sp <= '9'))
70                                                 sp++;
71                                         flush_buffer(tagger, sp - tagger);
72                                         date = strtoul(sp, &ep, 10);
73                                         tz = strtol(ep, NULL, 10);
74                                         sp = show_date(date, tz);
75                                         flush_buffer(sp, strlen(sp));
76                                         xwrite(1, "\n", 1);
77                                         break;
78                                 }
79                         }
80                         break;
81                 }
82                 if (cp < endp && *cp == '\n')
83                         /* end of header */
84                         break;
85         }
86         /* At this point, we have copied out the header up to the end of
87          * the tagger line and cp points at one past \n.  It could be the
88          * next header line after the tagger line, or it could be another
89          * \n that marks the end of the headers.  We need to copy out the
90          * remainder as is.
91          */
92         if (cp < endp)
93                 flush_buffer(cp, endp - cp);
94         return 0;
95 }
96
97 int cmd_cat_file(int argc, const char **argv, char **envp)
98 {
99         unsigned char sha1[20];
100         char type[20];
101         void *buf;
102         unsigned long size;
103         int opt;
104
105         setup_git_directory();
106         git_config(git_default_config);
107         if (argc != 3)
108                 usage("git-cat-file [-t|-s|-e|-p|<type>] <sha1>");
109         if (get_sha1(argv[2], sha1))
110                 die("Not a valid object name %s", argv[2]);
111
112         opt = 0;
113         if ( argv[1][0] == '-' ) {
114                 opt = argv[1][1];
115                 if ( !opt || argv[1][2] )
116                         opt = -1; /* Not a single character option */
117         }
118
119         buf = NULL;
120         switch (opt) {
121         case 't':
122                 if (!sha1_object_info(sha1, type, NULL)) {
123                         printf("%s\n", type);
124                         return 0;
125                 }
126                 break;
127
128         case 's':
129                 if (!sha1_object_info(sha1, type, &size)) {
130                         printf("%lu\n", size);
131                         return 0;
132                 }
133                 break;
134
135         case 'e':
136                 return !has_sha1_file(sha1);
137
138         case 'p':
139                 if (sha1_object_info(sha1, type, NULL))
140                         die("Not a valid object name %s", argv[2]);
141
142                 /* custom pretty-print here */
143                 if (!strcmp(type, tree_type))
144                         return cmd_ls_tree(2, argv + 1, NULL);
145
146                 buf = read_sha1_file(sha1, type, &size);
147                 if (!buf)
148                         die("Cannot read object %s", argv[2]);
149                 if (!strcmp(type, tag_type))
150                         return pprint_tag(sha1, buf, size);
151
152                 /* otherwise just spit out the data */
153                 break;
154         case 0:
155                 buf = read_object_with_reference(sha1, argv[1], &size, NULL);
156                 break;
157
158         default:
159                 die("git-cat-file: unknown option: %s\n", argv[1]);
160         }
161
162         if (!buf)
163                 die("git-cat-file %s: bad file", argv[2]);
164
165         flush_buffer(buf, size);
166         return 0;
167 }