t1510: setup case #4
[git/mjg.git] / wrapper.c
blobfd8ead33ed72c37e690ee1fc5b8568f629c95145
1 /*
2 * Various trivial helper wrappers around standard functions
3 */
4 #include "cache.h"
6 static void try_to_free_builtin(size_t size)
8 release_pack_memory(size, -1);
11 static void (*try_to_free_routine)(size_t size) = try_to_free_builtin;
13 try_to_free_t set_try_to_free_routine(try_to_free_t routine)
15 try_to_free_t old = try_to_free_routine;
16 try_to_free_routine = routine;
17 return old;
20 char *xstrdup(const char *str)
22 char *ret = strdup(str);
23 if (!ret) {
24 try_to_free_routine(strlen(str) + 1);
25 ret = strdup(str);
26 if (!ret)
27 die("Out of memory, strdup failed");
29 return ret;
32 void *xmalloc(size_t size)
34 void *ret = malloc(size);
35 if (!ret && !size)
36 ret = malloc(1);
37 if (!ret) {
38 try_to_free_routine(size);
39 ret = malloc(size);
40 if (!ret && !size)
41 ret = malloc(1);
42 if (!ret)
43 die("Out of memory, malloc failed (tried to allocate %lu bytes)",
44 (unsigned long)size);
46 #ifdef XMALLOC_POISON
47 memset(ret, 0xA5, size);
48 #endif
49 return ret;
52 void *xmallocz(size_t size)
54 void *ret;
55 if (size + 1 < size)
56 die("Data too large to fit into virtual memory space.");
57 ret = xmalloc(size + 1);
58 ((char*)ret)[size] = 0;
59 return ret;
63 * xmemdupz() allocates (len + 1) bytes of memory, duplicates "len" bytes of
64 * "data" to the allocated memory, zero terminates the allocated memory,
65 * and returns a pointer to the allocated memory. If the allocation fails,
66 * the program dies.
68 void *xmemdupz(const void *data, size_t len)
70 return memcpy(xmallocz(len), data, len);
73 char *xstrndup(const char *str, size_t len)
75 char *p = memchr(str, '\0', len);
76 return xmemdupz(str, p ? p - str : len);
79 void *xrealloc(void *ptr, size_t size)
81 void *ret = realloc(ptr, size);
82 if (!ret && !size)
83 ret = realloc(ptr, 1);
84 if (!ret) {
85 try_to_free_routine(size);
86 ret = realloc(ptr, size);
87 if (!ret && !size)
88 ret = realloc(ptr, 1);
89 if (!ret)
90 die("Out of memory, realloc failed");
92 return ret;
95 void *xcalloc(size_t nmemb, size_t size)
97 void *ret = calloc(nmemb, size);
98 if (!ret && (!nmemb || !size))
99 ret = calloc(1, 1);
100 if (!ret) {
101 try_to_free_routine(nmemb * size);
102 ret = calloc(nmemb, size);
103 if (!ret && (!nmemb || !size))
104 ret = calloc(1, 1);
105 if (!ret)
106 die("Out of memory, calloc failed");
108 return ret;
111 void *xmmap(void *start, size_t length,
112 int prot, int flags, int fd, off_t offset)
114 void *ret = mmap(start, length, prot, flags, fd, offset);
115 if (ret == MAP_FAILED) {
116 if (!length)
117 return NULL;
118 release_pack_memory(length, fd);
119 ret = mmap(start, length, prot, flags, fd, offset);
120 if (ret == MAP_FAILED)
121 die_errno("Out of memory? mmap failed");
123 return ret;
127 * xread() is the same a read(), but it automatically restarts read()
128 * operations with a recoverable error (EAGAIN and EINTR). xread()
129 * DOES NOT GUARANTEE that "len" bytes is read even if the data is available.
131 ssize_t xread(int fd, void *buf, size_t len)
133 ssize_t nr;
134 while (1) {
135 nr = read(fd, buf, len);
136 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
137 continue;
138 return nr;
143 * xwrite() is the same a write(), but it automatically restarts write()
144 * operations with a recoverable error (EAGAIN and EINTR). xwrite() DOES NOT
145 * GUARANTEE that "len" bytes is written even if the operation is successful.
147 ssize_t xwrite(int fd, const void *buf, size_t len)
149 ssize_t nr;
150 while (1) {
151 nr = write(fd, buf, len);
152 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
153 continue;
154 return nr;
158 ssize_t read_in_full(int fd, void *buf, size_t count)
160 char *p = buf;
161 ssize_t total = 0;
163 while (count > 0) {
164 ssize_t loaded = xread(fd, p, count);
165 if (loaded <= 0)
166 return total ? total : loaded;
167 count -= loaded;
168 p += loaded;
169 total += loaded;
172 return total;
175 ssize_t write_in_full(int fd, const void *buf, size_t count)
177 const char *p = buf;
178 ssize_t total = 0;
180 while (count > 0) {
181 ssize_t written = xwrite(fd, p, count);
182 if (written < 0)
183 return -1;
184 if (!written) {
185 errno = ENOSPC;
186 return -1;
188 count -= written;
189 p += written;
190 total += written;
193 return total;
196 int xdup(int fd)
198 int ret = dup(fd);
199 if (ret < 0)
200 die_errno("dup failed");
201 return ret;
204 FILE *xfdopen(int fd, const char *mode)
206 FILE *stream = fdopen(fd, mode);
207 if (stream == NULL)
208 die_errno("Out of memory? fdopen failed");
209 return stream;
212 int xmkstemp(char *template)
214 int fd;
216 fd = mkstemp(template);
217 if (fd < 0)
218 die_errno("Unable to create temporary file");
219 return fd;
222 int xmkstemp_mode(char *template, int mode)
224 int fd;
226 fd = git_mkstemp_mode(template, mode);
227 if (fd < 0)
228 die_errno("Unable to create temporary file");
229 return fd;
233 * zlib wrappers to make sure we don't silently miss errors
234 * at init time.
236 void git_inflate_init(z_streamp strm)
238 const char *err;
240 switch (inflateInit(strm)) {
241 case Z_OK:
242 return;
244 case Z_MEM_ERROR:
245 err = "out of memory";
246 break;
247 case Z_VERSION_ERROR:
248 err = "wrong version";
249 break;
250 default:
251 err = "error";
253 die("inflateInit: %s (%s)", err, strm->msg ? strm->msg : "no message");
256 void git_inflate_end(z_streamp strm)
258 if (inflateEnd(strm) != Z_OK)
259 error("inflateEnd: %s", strm->msg ? strm->msg : "failed");
262 int git_inflate(z_streamp strm, int flush)
264 int ret = inflate(strm, flush);
265 const char *err;
267 switch (ret) {
268 /* Out of memory is fatal. */
269 case Z_MEM_ERROR:
270 die("inflate: out of memory");
272 /* Data corruption errors: we may want to recover from them (fsck) */
273 case Z_NEED_DICT:
274 err = "needs dictionary"; break;
275 case Z_DATA_ERROR:
276 err = "data stream error"; break;
277 case Z_STREAM_ERROR:
278 err = "stream consistency error"; break;
279 default:
280 err = "unknown error"; break;
282 /* Z_BUF_ERROR: normal, needs more space in the output buffer */
283 case Z_BUF_ERROR:
284 case Z_OK:
285 case Z_STREAM_END:
286 return ret;
288 error("inflate: %s (%s)", err, strm->msg ? strm->msg : "no message");
289 return ret;
292 int odb_mkstemp(char *template, size_t limit, const char *pattern)
294 int fd;
296 * we let the umask do its job, don't try to be more
297 * restrictive except to remove write permission.
299 int mode = 0444;
300 snprintf(template, limit, "%s/%s",
301 get_object_directory(), pattern);
302 fd = git_mkstemp_mode(template, mode);
303 if (0 <= fd)
304 return fd;
306 /* slow path */
307 /* some mkstemp implementations erase template on failure */
308 snprintf(template, limit, "%s/%s",
309 get_object_directory(), pattern);
310 safe_create_leading_directories(template);
311 return xmkstemp_mode(template, mode);
314 int odb_pack_keep(char *name, size_t namesz, unsigned char *sha1)
316 int fd;
318 snprintf(name, namesz, "%s/pack/pack-%s.keep",
319 get_object_directory(), sha1_to_hex(sha1));
320 fd = open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
321 if (0 <= fd)
322 return fd;
324 /* slow path */
325 safe_create_leading_directories(name);
326 return open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
329 static int warn_if_unremovable(const char *op, const char *file, int rc)
331 if (rc < 0) {
332 int err = errno;
333 if (ENOENT != err) {
334 warning("unable to %s %s: %s",
335 op, file, strerror(errno));
336 errno = err;
339 return rc;
342 int unlink_or_warn(const char *file)
344 return warn_if_unremovable("unlink", file, unlink(file));
347 int rmdir_or_warn(const char *file)
349 return warn_if_unremovable("rmdir", file, rmdir(file));
352 int remove_or_warn(unsigned int mode, const char *file)
354 return S_ISGITLINK(mode) ? rmdir_or_warn(file) : unlink_or_warn(file);