Merge branch 'mh/update-ref-batch-create-fix'
[git] / builtin / replace.c
1 /*
2  * Builtin "git replace"
3  *
4  * Copyright (c) 2008 Christian Couder <chriscool@tuxfamily.org>
5  *
6  * Based on builtin/tag.c by Kristian Høgsberg <krh@redhat.com>
7  * and Carlos Rica <jasampler@gmail.com> that was itself based on
8  * git-tag.sh and mktag.c by Linus Torvalds.
9  */
10
11 #include "cache.h"
12 #include "builtin.h"
13 #include "refs.h"
14 #include "parse-options.h"
15
16 static const char * const git_replace_usage[] = {
17         N_("git replace [-f] <object> <replacement>"),
18         N_("git replace -d <object>..."),
19         N_("git replace [--format=<format>] [-l [<pattern>]]"),
20         NULL
21 };
22
23 enum replace_format {
24       REPLACE_FORMAT_SHORT,
25       REPLACE_FORMAT_MEDIUM,
26       REPLACE_FORMAT_LONG
27 };
28
29 struct show_data {
30         const char *pattern;
31         enum replace_format format;
32 };
33
34 static int show_reference(const char *refname, const unsigned char *sha1,
35                           int flag, void *cb_data)
36 {
37         struct show_data *data = cb_data;
38
39         if (!wildmatch(data->pattern, refname, 0, NULL)) {
40                 if (data->format == REPLACE_FORMAT_SHORT)
41                         printf("%s\n", refname);
42                 else if (data->format == REPLACE_FORMAT_MEDIUM)
43                         printf("%s -> %s\n", refname, sha1_to_hex(sha1));
44                 else { /* data->format == REPLACE_FORMAT_LONG */
45                         unsigned char object[20];
46                         enum object_type obj_type, repl_type;
47
48                         if (get_sha1(refname, object))
49                                 return error("Failed to resolve '%s' as a valid ref.", refname);
50
51                         obj_type = sha1_object_info(object, NULL);
52                         repl_type = sha1_object_info(sha1, NULL);
53
54                         printf("%s (%s) -> %s (%s)\n", refname, typename(obj_type),
55                                sha1_to_hex(sha1), typename(repl_type));
56                 }
57         }
58
59         return 0;
60 }
61
62 static int list_replace_refs(const char *pattern, const char *format)
63 {
64         struct show_data data;
65
66         if (pattern == NULL)
67                 pattern = "*";
68         data.pattern = pattern;
69
70         if (format == NULL || *format == '\0' || !strcmp(format, "short"))
71                 data.format = REPLACE_FORMAT_SHORT;
72         else if (!strcmp(format, "medium"))
73                 data.format = REPLACE_FORMAT_MEDIUM;
74         else if (!strcmp(format, "long"))
75                 data.format = REPLACE_FORMAT_LONG;
76         else
77                 die("invalid replace format '%s'\n"
78                     "valid formats are 'short', 'medium' and 'long'\n",
79                     format);
80
81         for_each_replace_ref(show_reference, (void *) &data);
82
83         return 0;
84 }
85
86 typedef int (*each_replace_name_fn)(const char *name, const char *ref,
87                                     const unsigned char *sha1);
88
89 static int for_each_replace_name(const char **argv, each_replace_name_fn fn)
90 {
91         const char **p, *full_hex;
92         char ref[PATH_MAX];
93         int had_error = 0;
94         unsigned char sha1[20];
95
96         for (p = argv; *p; p++) {
97                 if (get_sha1(*p, sha1)) {
98                         error("Failed to resolve '%s' as a valid ref.", *p);
99                         had_error = 1;
100                         continue;
101                 }
102                 full_hex = sha1_to_hex(sha1);
103                 snprintf(ref, sizeof(ref), "refs/replace/%s", full_hex);
104                 /* read_ref() may reuse the buffer */
105                 full_hex = ref + strlen("refs/replace/");
106                 if (read_ref(ref, sha1)) {
107                         error("replace ref '%s' not found.", full_hex);
108                         had_error = 1;
109                         continue;
110                 }
111                 if (fn(full_hex, ref, sha1))
112                         had_error = 1;
113         }
114         return had_error;
115 }
116
117 static int delete_replace_ref(const char *name, const char *ref,
118                               const unsigned char *sha1)
119 {
120         if (delete_ref(ref, sha1, 0))
121                 return 1;
122         printf("Deleted replace ref '%s'\n", name);
123         return 0;
124 }
125
126 static int replace_object(const char *object_ref, const char *replace_ref,
127                           int force)
128 {
129         unsigned char object[20], prev[20], repl[20];
130         enum object_type obj_type, repl_type;
131         char ref[PATH_MAX];
132         struct ref_lock *lock;
133
134         if (get_sha1(object_ref, object))
135                 die("Failed to resolve '%s' as a valid ref.", object_ref);
136         if (get_sha1(replace_ref, repl))
137                 die("Failed to resolve '%s' as a valid ref.", replace_ref);
138
139         if (snprintf(ref, sizeof(ref),
140                      "refs/replace/%s",
141                      sha1_to_hex(object)) > sizeof(ref) - 1)
142                 die("replace ref name too long: %.*s...", 50, ref);
143         if (check_refname_format(ref, 0))
144                 die("'%s' is not a valid ref name.", ref);
145
146         obj_type = sha1_object_info(object, NULL);
147         repl_type = sha1_object_info(repl, NULL);
148         if (!force && obj_type != repl_type)
149                 die("Objects must be of the same type.\n"
150                     "'%s' points to a replaced object of type '%s'\n"
151                     "while '%s' points to a replacement object of type '%s'.",
152                     object_ref, typename(obj_type),
153                     replace_ref, typename(repl_type));
154
155         if (read_ref(ref, prev))
156                 hashclr(prev);
157         else if (!force)
158                 die("replace ref '%s' already exists", ref);
159
160         lock = lock_any_ref_for_update(ref, prev, 0, NULL);
161         if (!lock)
162                 die("%s: cannot lock the ref", ref);
163         if (write_ref_sha1(lock, repl, NULL) < 0)
164                 die("%s: cannot update the ref", ref);
165
166         return 0;
167 }
168
169 int cmd_replace(int argc, const char **argv, const char *prefix)
170 {
171         int list = 0, delete = 0, force = 0;
172         const char *format = NULL;
173         struct option options[] = {
174                 OPT_BOOL('l', "list", &list, N_("list replace refs")),
175                 OPT_BOOL('d', "delete", &delete, N_("delete replace refs")),
176                 OPT_BOOL('f', "force", &force, N_("replace the ref if it exists")),
177                 OPT_STRING(0, "format", &format, N_("format"), N_("use this format")),
178                 OPT_END()
179         };
180
181         check_replace_refs = 0;
182
183         argc = parse_options(argc, argv, prefix, options, git_replace_usage, 0);
184
185         if (list && delete)
186                 usage_msg_opt("-l and -d cannot be used together",
187                               git_replace_usage, options);
188
189         if (format && delete)
190                 usage_msg_opt("--format and -d cannot be used together",
191                               git_replace_usage, options);
192
193         if (force && (list || delete))
194                 usage_msg_opt("-f cannot be used with -d or -l",
195                               git_replace_usage, options);
196
197         /* Delete refs */
198         if (delete) {
199                 if (argc < 1)
200                         usage_msg_opt("-d needs at least one argument",
201                                       git_replace_usage, options);
202                 return for_each_replace_name(argv, delete_replace_ref);
203         }
204
205         /* Replace object */
206         if (!list && argc) {
207                 if (argc != 2)
208                         usage_msg_opt("bad number of arguments",
209                                       git_replace_usage, options);
210                 if (format)
211                         usage_msg_opt("--format cannot be used when not listing",
212                                       git_replace_usage, options);
213                 return replace_object(argv[0], argv[1], force);
214         }
215
216         /* List refs, even if "list" is not set */
217         if (argc > 1)
218                 usage_msg_opt("only one pattern can be given with -l",
219                               git_replace_usage, options);
220         if (force)
221                 usage_msg_opt("-f needs some arguments",
222                               git_replace_usage, options);
223
224         return list_replace_refs(argv[0], format);
225 }