summaryrefslogtreecommitdiff
path: root/builtin/replace.c
blob: 80b152a86c4ea3d003b113ae0402a5f1fb701b3d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
/*
 * Builtin "git replace"
 *
 * Copyright (c) 2008 Christian Couder <chriscool@tuxfamily.org>
 *
 * Based on builtin/tag.c by Kristian Høgsberg <krh@redhat.com>
 * and Carlos Rica <jasampler@gmail.com> that was itself based on
 * git-tag.sh and mktag.c by Linus Torvalds.
 */

#include "cache.h"
#include "builtin.h"
#include "refs.h"
#include "parse-options.h"

static const char * const git_replace_usage[] = {
	N_("git replace [-f] <object> <replacement>"),
	N_("git replace -d <object>..."),
	N_("git replace [--format=<format>] [-l [<pattern>]]"),
	NULL
};

enum replace_format {
      REPLACE_FORMAT_SHORT,
      REPLACE_FORMAT_MEDIUM,
      REPLACE_FORMAT_LONG
};

struct show_data {
	const char *pattern;
	enum replace_format format;
};

static int show_reference(const char *refname, const unsigned char *sha1,
			  int flag, void *cb_data)
{
	struct show_data *data = cb_data;

	if (!wildmatch(data->pattern, refname, 0, NULL)) {
		if (data->format == REPLACE_FORMAT_SHORT)
			printf("%s\n", refname);
		else if (data->format == REPLACE_FORMAT_MEDIUM)
			printf("%s -> %s\n", refname, sha1_to_hex(sha1));
		else { /* data->format == REPLACE_FORMAT_LONG */
			unsigned char object[20];
			enum object_type obj_type, repl_type;

			if (get_sha1(refname, object))
				return error("Failed to resolve '%s' as a valid ref.", refname);

			obj_type = sha1_object_info(object, NULL);
			repl_type = sha1_object_info(sha1, NULL);

			printf("%s (%s) -> %s (%s)\n", refname, typename(obj_type),
			       sha1_to_hex(sha1), typename(repl_type));
		}
	}

	return 0;
}

static int list_replace_refs(const char *pattern, const char *format)
{
	struct show_data data;

	if (pattern == NULL)
		pattern = "*";
	data.pattern = pattern;

	if (format == NULL || *format == '\0' || !strcmp(format, "short"))
		data.format = REPLACE_FORMAT_SHORT;
	else if (!strcmp(format, "medium"))
		data.format = REPLACE_FORMAT_MEDIUM;
	else if (!strcmp(format, "long"))
		data.format = REPLACE_FORMAT_LONG;
	else
		die("invalid replace format '%s'\n"
		    "valid formats are 'short', 'medium' and 'long'\n",
		    format);

	for_each_replace_ref(show_reference, (void *) &data);

	return 0;
}

typedef int (*each_replace_name_fn)(const char *name, const char *ref,
				    const unsigned char *sha1);

static int for_each_replace_name(const char **argv, each_replace_name_fn fn)
{
	const char **p, *full_hex;
	char ref[PATH_MAX];
	int had_error = 0;
	unsigned char sha1[20];

	for (p = argv; *p; p++) {
		if (get_sha1(*p, sha1)) {
			error("Failed to resolve '%s' as a valid ref.", *p);
			had_error = 1;
			continue;
		}
		full_hex = sha1_to_hex(sha1);
		snprintf(ref, sizeof(ref), "refs/replace/%s", full_hex);
		/* read_ref() may reuse the buffer */
		full_hex = ref + strlen("refs/replace/");
		if (read_ref(ref, sha1)) {
			error("replace ref '%s' not found.", full_hex);
			had_error = 1;
			continue;
		}
		if (fn(full_hex, ref, sha1))
			had_error = 1;
	}
	return had_error;
}

static int delete_replace_ref(const char *name, const char *ref,
			      const unsigned char *sha1)
{
	if (delete_ref(ref, sha1, 0))
		return 1;
	printf("Deleted replace ref '%s'\n", name);
	return 0;
}

static int replace_object(const char *object_ref, const char *replace_ref,
			  int force)
{
	unsigned char object[20], prev[20], repl[20];
	enum object_type obj_type, repl_type;
	char ref[PATH_MAX];
	struct ref_lock *lock;

	if (get_sha1(object_ref, object))
		die("Failed to resolve '%s' as a valid ref.", object_ref);
	if (get_sha1(replace_ref, repl))
		die("Failed to resolve '%s' as a valid ref.", replace_ref);

	if (snprintf(ref, sizeof(ref),
		     "refs/replace/%s",
		     sha1_to_hex(object)) > sizeof(ref) - 1)
		die("replace ref name too long: %.*s...", 50, ref);
	if (check_refname_format(ref, 0))
		die("'%s' is not a valid ref name.", ref);

	obj_type = sha1_object_info(object, NULL);
	repl_type = sha1_object_info(repl, NULL);
	if (!force && obj_type != repl_type)
		die("Objects must be of the same type.\n"
		    "'%s' points to a replaced object of type '%s'\n"
		    "while '%s' points to a replacement object of type '%s'.",
		    object_ref, typename(obj_type),
		    replace_ref, typename(repl_type));

	if (read_ref(ref, prev))
		hashclr(prev);
	else if (!force)
		die("replace ref '%s' already exists", ref);

	lock = lock_any_ref_for_update(ref, prev, 0, NULL);
	if (!lock)
		die("%s: cannot lock the ref", ref);
	if (write_ref_sha1(lock, repl, NULL) < 0)
		die("%s: cannot update the ref", ref);

	return 0;
}

int cmd_replace(int argc, const char **argv, const char *prefix)
{
	int list = 0, delete = 0, force = 0;
	const char *format = NULL;
	struct option options[] = {
		OPT_BOOL('l', "list", &list, N_("list replace refs")),
		OPT_BOOL('d', "delete", &delete, N_("delete replace refs")),
		OPT_BOOL('f', "force", &force, N_("replace the ref if it exists")),
		OPT_STRING(0, "format", &format, N_("format"), N_("use this format")),
		OPT_END()
	};

	read_replace_refs = 0;

	argc = parse_options(argc, argv, prefix, options, git_replace_usage, 0);

	if (list && delete)
		usage_msg_opt("-l and -d cannot be used together",
			      git_replace_usage, options);

	if (format && delete)
		usage_msg_opt("--format and -d cannot be used together",
			      git_replace_usage, options);

	if (force && (list || delete))
		usage_msg_opt("-f cannot be used with -d or -l",
			      git_replace_usage, options);

	/* Delete refs */
	if (delete) {
		if (argc < 1)
			usage_msg_opt("-d needs at least one argument",
				      git_replace_usage, options);
		return for_each_replace_name(argv, delete_replace_ref);
	}

	/* Replace object */
	if (!list && argc) {
		if (argc != 2)
			usage_msg_opt("bad number of arguments",
				      git_replace_usage, options);
		if (format)
			usage_msg_opt("--format cannot be used when not listing",
				      git_replace_usage, options);
		return replace_object(argv[0], argv[1], force);
	}

	/* List refs, even if "list" is not set */
	if (argc > 1)
		usage_msg_opt("only one pattern can be given with -l",
			      git_replace_usage, options);
	if (force)
		usage_msg_opt("-f needs some arguments",
			      git_replace_usage, options);

	return list_replace_refs(argv[0], format);
}