compat/bswap.h: fix endianness detection
[git/git.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 }