summaryrefslogtreecommitdiff
path: root/wrapper.c
blob: 0e3e20a3fd38f6f99da44483ee0bb9753f2b217a (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
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
/*
 * Various trivial helper wrappers around standard functions
 */
#include "cache.h"

char *xstrdup(const char *str)
{
	char *ret = strdup(str);
	if (!ret) {
		release_pack_memory(strlen(str) + 1, -1);
		ret = strdup(str);
		if (!ret)
			die("Out of memory, strdup failed");
	}
	return ret;
}

void *xmalloc(size_t size)
{
	void *ret = malloc(size);
	if (!ret && !size)
		ret = malloc(1);
	if (!ret) {
		release_pack_memory(size, -1);
		ret = malloc(size);
		if (!ret && !size)
			ret = malloc(1);
		if (!ret)
			die("Out of memory, malloc failed");
	}
#ifdef XMALLOC_POISON
	memset(ret, 0xA5, size);
#endif
	return ret;
}

void *xmallocz(size_t size)
{
	void *ret;
	if (size + 1 < size)
		die("Data too large to fit into virtual memory space.");
	ret = xmalloc(size + 1);
	((char*)ret)[size] = 0;
	return ret;
}

/*
 * xmemdupz() allocates (len + 1) bytes of memory, duplicates "len" bytes of
 * "data" to the allocated memory, zero terminates the allocated memory,
 * and returns a pointer to the allocated memory. If the allocation fails,
 * the program dies.
 */
void *xmemdupz(const void *data, size_t len)
{
	return memcpy(xmallocz(len), data, len);
}

char *xstrndup(const char *str, size_t len)
{
	char *p = memchr(str, '\0', len);
	return xmemdupz(str, p ? p - str : len);
}

void *xrealloc(void *ptr, size_t size)
{
	void *ret = realloc(ptr, size);
	if (!ret && !size)
		ret = realloc(ptr, 1);
	if (!ret) {
		release_pack_memory(size, -1);
		ret = realloc(ptr, size);
		if (!ret && !size)
			ret = realloc(ptr, 1);
		if (!ret)
			die("Out of memory, realloc failed");
	}
	return ret;
}

void *xcalloc(size_t nmemb, size_t size)
{
	void *ret = calloc(nmemb, size);
	if (!ret && (!nmemb || !size))
		ret = calloc(1, 1);
	if (!ret) {
		release_pack_memory(nmemb * size, -1);
		ret = calloc(nmemb, size);
		if (!ret && (!nmemb || !size))
			ret = calloc(1, 1);
		if (!ret)
			die("Out of memory, calloc failed");
	}
	return ret;
}

void *xmmap(void *start, size_t length,
	int prot, int flags, int fd, off_t offset)
{
	void *ret = mmap(start, length, prot, flags, fd, offset);
	if (ret == MAP_FAILED) {
		if (!length)
			return NULL;
		release_pack_memory(length, fd);
		ret = mmap(start, length, prot, flags, fd, offset);
		if (ret == MAP_FAILED)
			die_errno("Out of memory? mmap failed");
	}
	return ret;
}

/*
 * xread() is the same a read(), but it automatically restarts read()
 * operations with a recoverable error (EAGAIN and EINTR). xread()
 * DOES NOT GUARANTEE that "len" bytes is read even if the data is available.
 */
ssize_t xread(int fd, void *buf, size_t len)
{
	ssize_t nr;
	while (1) {
		nr = read(fd, buf, len);
		if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
			continue;
		return nr;
	}
}

/*
 * xwrite() is the same a write(), but it automatically restarts write()
 * operations with a recoverable error (EAGAIN and EINTR). xwrite() DOES NOT
 * GUARANTEE that "len" bytes is written even if the operation is successful.
 */
ssize_t xwrite(int fd, const void *buf, size_t len)
{
	ssize_t nr;
	while (1) {
		nr = write(fd, buf, len);
		if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
			continue;
		return nr;
	}
}

ssize_t read_in_full(int fd, void *buf, size_t count)
{
	char *p = buf;
	ssize_t total = 0;

	while (count > 0) {
		ssize_t loaded = xread(fd, p, count);
		if (loaded <= 0)
			return total ? total : loaded;
		count -= loaded;
		p += loaded;
		total += loaded;
	}

	return total;
}

ssize_t write_in_full(int fd, const void *buf, size_t count)
{
	const char *p = buf;
	ssize_t total = 0;

	while (count > 0) {
		ssize_t written = xwrite(fd, p, count);
		if (written < 0)
			return -1;
		if (!written) {
			errno = ENOSPC;
			return -1;
		}
		count -= written;
		p += written;
		total += written;
	}

	return total;
}

int xdup(int fd)
{
	int ret = dup(fd);
	if (ret < 0)
		die_errno("dup failed");
	return ret;
}

FILE *xfdopen(int fd, const char *mode)
{
	FILE *stream = fdopen(fd, mode);
	if (stream == NULL)
		die_errno("Out of memory? fdopen failed");
	return stream;
}

int xmkstemp(char *template)
{
	int fd;

	fd = mkstemp(template);
	if (fd < 0)
		die_errno("Unable to create temporary file");
	return fd;
}

/*
 * zlib wrappers to make sure we don't silently miss errors
 * at init time.
 */
void git_inflate_init(z_streamp strm)
{
	const char *err;

	switch (inflateInit(strm)) {
	case Z_OK:
		return;

	case Z_MEM_ERROR:
		err = "out of memory";
		break;
	case Z_VERSION_ERROR:
		err = "wrong version";
		break;
	default:
		err = "error";
	}
	die("inflateInit: %s (%s)", err, strm->msg ? strm->msg : "no message");
}

void git_inflate_end(z_streamp strm)
{
	if (inflateEnd(strm) != Z_OK)
		error("inflateEnd: %s", strm->msg ? strm->msg : "failed");
}

int git_inflate(z_streamp strm, int flush)
{
	int ret = inflate(strm, flush);
	const char *err;

	switch (ret) {
	/* Out of memory is fatal. */
	case Z_MEM_ERROR:
		die("inflate: out of memory");

	/* Data corruption errors: we may want to recover from them (fsck) */
	case Z_NEED_DICT:
		err = "needs dictionary"; break;
	case Z_DATA_ERROR:
		err = "data stream error"; break;
	case Z_STREAM_ERROR:
		err = "stream consistency error"; break;
	default:
		err = "unknown error"; break;

	/* Z_BUF_ERROR: normal, needs more space in the output buffer */
	case Z_BUF_ERROR:
	case Z_OK:
	case Z_STREAM_END:
		return ret;
	}
	error("inflate: %s (%s)", err, strm->msg ? strm->msg : "no message");
	return ret;
}

int odb_mkstemp(char *template, size_t limit, const char *pattern)
{
	int fd;

	snprintf(template, limit, "%s/%s",
		 get_object_directory(), pattern);
	fd = mkstemp(template);
	if (0 <= fd)
		return fd;

	/* slow path */
	/* some mkstemp implementations erase template on failure */
	snprintf(template, limit, "%s/%s",
		 get_object_directory(), pattern);
	safe_create_leading_directories(template);
	return xmkstemp(template);
}

int odb_pack_keep(char *name, size_t namesz, unsigned char *sha1)
{
	int fd;

	snprintf(name, namesz, "%s/pack/pack-%s.keep",
		 get_object_directory(), sha1_to_hex(sha1));
	fd = open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
	if (0 <= fd)
		return fd;

	/* slow path */
	safe_create_leading_directories(name);
	return open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
}

int unlink_or_warn(const char *file)
{
	int rc = unlink(file);

	if (rc < 0) {
		int err = errno;
		if (ENOENT != err) {
			warning("unable to unlink %s: %s",
				file, strerror(errno));
			errno = err;
		}
	}
	return rc;
}