jscoverage/trunk/util.c

/*
    util.c - general purpose utility routines
    Copyright (C) 2007, 2008 siliconforks.com

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License along
    with this program; if not, write to the Free Software Foundation, Inc.,
    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#define _GNU_SOURCE

#include <config.h>

#include "util.h"

#include <assert.h>
#include <errno.h>
#include <limits.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <strings.h>

#include <dirent.h>
#include <libgen.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

const char * program = NULL;

void fatal(const char * format, ...) {
  fprintf(stderr, "%s: ", program);
  va_list ap;
  va_start(ap, format);
  vfprintf(stderr, format, ap);
  va_end(ap);
  fputc('\n', stderr);
  exit(EXIT_FAILURE);
}

void fatal_command_line(const char * format, ...) {
  fprintf(stderr, "%s: ", program);
  va_list ap;
  va_start(ap, format);
  vfprintf(stderr, format, ap);
  va_end(ap);
  fputc('\n', stderr);
  fprintf(stderr, "Try `%s --help' for more information.\n", program);
  exit(EXIT_FAILURE);
}

void fatal_source(const char * source_file, unsigned int line_number, const char * format, ...) {
  fprintf(stderr, "%s:%s:%u: ", program, source_file, line_number);
  va_list ap;
  va_start(ap, format);
  vfprintf(stderr, format, ap);
  va_end(ap);
  fputc('\n', stderr);
  exit(EXIT_FAILURE);
}

void version(void) {
  printf("%s %s\n", program, VERSION);
  printf("Character encoding support: ");
#if HAVE_ICONV
  printf("iconv\n");
#elif HAVE_MULTIBYTETOWIDECHAR
  printf("MultiByteToWideChar\n");
#else
  printf("none\n");
#endif
  exit(EXIT_SUCCESS);
}

size_t addst(size_t x, size_t y) {
  if (SIZE_MAX - x < y) {
    fatal("integer overflow");
  }
  return x + y;
}

size_t mulst(size_t x, size_t y) {
  if (x == 0 || y == 0) {
    return 0;
  }
  if (SIZE_MAX / x < y) {
    fatal("integer overflow");
  }
  return x * y;
}

void * xmalloc(size_t size) {
  void * result = malloc(size);
  if (result == NULL) {
    fatal("out of memory");
  }
  return result;
}

void * xrealloc(void * p, size_t size) {
  void * result = realloc(p, size);
  if (result == NULL) {
    fatal("out of memory");
  }
  return result;
}

char * xstrdup(const char * s) {
  char * result = strdup(s);
  if (result == NULL) {
    fatal("out of memory");
  }
  return result;
}

char * xstrndup(const char * s, size_t size) {
  char * result = strndup(s, size);
  if (result == NULL) {
    fatal("out of memory");
  }
  return result;
}

int xasprintf(char ** s, const char * template, ...) {
  va_list a;
  va_start(a, template);
  int result = vasprintf(s, template, a);
  va_end(a);
  if (result < 0) {
    fatal("out of memory");
  }
  return result;
}

char * xgetcwd(void) {
  char * result = getcwd(NULL, 0);
  if (result == NULL) {
    fatal("out of memory");
  }
  return result;
}

FILE * xfopen(const char * file, const char * mode) {
  FILE * result = fopen(file, mode);
  if (result == NULL) {
    fatal("cannot open file: %s", file);
  }
  return result;
}

DIR * xopendir(const char * directory) {
  DIR * result = opendir(directory);
  if (result == NULL) {
    fatal("cannot open directory: %s", directory);
  }
  return result;
}

void xlstat(const char * file, struct stat * buf) {
#ifdef _WIN32
  return xstat(file, buf);
#else
  if (lstat(file, buf) == -1) {
    fatal("cannot stat file: %s", file);
  }
#endif
}

void xstat(const char * file, struct stat * buf) {
  if (stat(file, buf) == -1) {
    fatal("cannot stat file: %s", file);
  }
}

void xmkdir(const char * directory) {
  int result;
#ifdef _WIN32
  result = mkdir(directory);
#else
  result = mkdir(directory, 0755);
#endif
  if (result == -1) {
    fatal("cannot create directory: %s", directory);
  }
}

void mkdir_if_necessary(const char * directory) {
  struct stat buf;
  if (stat(directory, &buf) == 0) {
    if (! S_ISDIR(buf.st_mode)) {
      fatal("not a directory: %s", directory);
    }
  }
  else {
    if (errno == ENOENT) {
      xmkdir(directory);
    }
    else {
      fatal("cannot stat directory: %s", directory);
    }
  }
}

void mkdirs(const char * directory) {
  char * d = xmalloc(strlen(directory) + 1);
  for (const char * p = directory; *p != '\0'; p++) {
    if (*p == '/' && p > directory) {
      strncpy(d, directory, p - directory);
      d[p - directory] = '\0';
      mkdir_if_necessary(d);
    }
  }
  mkdir_if_necessary(directory);
  free(d);
}

void xchdir(const char * directory) {
  if (chdir(directory) == -1) {
    fatal("cannot change directory: %s", directory);
  }
}

bool str_starts_with(const char * string, const char * prefix) {
  const char * string_ptr = string;
  const char * prefix_ptr = prefix;
  while (*string_ptr != '\0' && *prefix_ptr != '\0') {
    if (*string_ptr != *prefix_ptr) {
      return false;
    }
    string_ptr++;
    prefix_ptr++;
  }
  if (*string_ptr == '\0' && *prefix_ptr != '\0') {
    return false;
  }
  return true;
}

bool str_ends_with(const char * string, const char * suffix) {
  size_t string_length = strlen(string);
  size_t suffix_length = strlen(suffix);
  if (string_length < suffix_length) {
    return false;
  }
  return strcmp(string + string_length - suffix_length, suffix) == 0;
}

char * make_path(const char * parent, const char * relative_path) {
  size_t parent_length = strlen(parent);
  size_t relative_path_length = strlen(relative_path);
  size_t result_length = addst(parent_length, relative_path_length);
  result_length = addst(result_length, 2);
  char * result = xmalloc(result_length);
  strcpy(result, parent);
  result[parent_length] = '/';
  strcpy(result + parent_length + 1, relative_path);
  return result;
}

char * make_canonical_path(const char * relative_path) {
  char * original_directory = xgetcwd();
  char * base = make_basename(relative_path);
  char * dir = make_dirname(relative_path);

  xchdir(dir);
  char * canonical_dir = xgetcwd();
  char * result = make_path(canonical_dir, base);

  free(canonical_dir);
  free(base);
  free(dir);
  xchdir(original_directory);
  free(original_directory);

  return result;
}

char * make_basename(const char * path) {
  char * copy = xstrdup(path);
  char * result = xstrdup(basename(copy));
  free(copy);
  return result;
}

char * make_dirname(const char * path) {
  char * copy = xstrdup(path);
  char * result = xstrdup(dirname(copy));
  free(copy);
  return result;
}

int is_same_file(const char * file1, const char * file2) {
#ifdef _WIN32
#define FILECMP strcasecmp
#else
#define FILECMP strcmp
#endif
  if (FILECMP(file1, file2) == 0) {
    return 1;
  }

  char * canonical1 = make_canonical_path(file1);
  char * canonical2 = make_canonical_path(file2);
  int cmp = FILECMP(canonical1, canonical2);
  free(canonical1);
  free(canonical2);
  if (cmp == 0) {
    return 1;
  }

#ifndef _WIN32
  struct stat buf1;
  if (stat(file1, &buf1) == -1) {
    if (errno == ENOENT) {
      return 0;
    }
    else {
      fatal("cannot stat file: %s", file1);
    }
  }
  struct stat buf2;
  if (stat(file2, &buf2) == -1) {
    if (errno == ENOENT) {
      return 0;
    }
    else {
      fatal("cannot stat file: %s", file2);
    }
  }
  if (buf1.st_dev == buf2.st_dev &&
      buf1.st_ino == buf2.st_ino) {
    return 1;
  }
#endif
  return 0;
#undef FILECMP
}

int contains_file(const char * file1, const char * file2) {
  int result = 0;
  char * ancestor = make_canonical_path(file1);
  char * d = make_canonical_path(file2);
  char * parent = make_dirname(d);
  while (strcmp(d, parent) != 0) {
    if (is_same_file(ancestor, parent)) {
      result = 1;
      break;
    }
    free(d);
    d = parent;
    parent = make_dirname(d);
  }
  free(d);
  free(parent);
  free(ancestor);
  return result;
}

void copy_stream(FILE * source, FILE * destination) {
  unsigned char buffer[8192];
  for (;;) {
    int bytes_read = fread(buffer, 1, sizeof(buffer), source);
    if (bytes_read == 0) {
      break;
    }
    fwrite(buffer, 1, bytes_read, destination);
  }
}

void copy_file(const char * source_file, const char * destination_file) {
  FILE * source = xfopen(source_file, "rb");
  FILE * destination = xfopen(destination_file, "wb");

  copy_stream(source, destination);

#ifndef _WIN32
  /* copy permissions */
  struct stat buf;
  if (fstat(fileno(source), &buf) == -1) {
    fatal("cannot stat file: %s", source_file);
  }
  fchmod(fileno(destination), buf.st_mode);
#endif

  fclose(source);
  fclose(destination);
}

bool directory_is_empty(const char * directory) {
  bool result = true;
  DIR * dir = xopendir(directory);
  struct dirent * e;
  while ((e = readdir(dir)) != NULL) {
    if (strcmp(e->d_name, ".") != 0 &&
        strcmp(e->d_name, "..") != 0) {
      result = false;
      break;
    }
  }
  closedir(dir);
  return result;
}

static struct DirListEntry * recursive_dir_list(const char * root, const char * directory_wrt_root, struct DirListEntry * head) {
  char * directory = directory_wrt_root == NULL? xstrdup(root): make_path(root, directory_wrt_root);
  DIR * dir = xopendir(directory);
  struct dirent * e;
  while ((e = readdir(dir)) != NULL) {
    if (strcmp(e->d_name, ".") == 0 ||
        strcmp(e->d_name, "..") == 0) {
      continue;
    }
    char * entry = make_path(directory, e->d_name);
    char * entry_wrt_root = directory_wrt_root == NULL? xstrdup(e->d_name): make_path(directory_wrt_root, e->d_name);
    struct stat buf;
    xlstat(entry, &buf);
    if (S_ISREG(buf.st_mode)) {
      struct DirListEntry * p = xmalloc(sizeof(struct DirListEntry));
      p->name = entry_wrt_root;
      p->next = head;
      head = p;
    }
    else if (S_ISDIR(buf.st_mode)) {
      head = recursive_dir_list(root, entry_wrt_root, head);
      free(entry_wrt_root);
    }
#ifndef _WIN32
    else if (S_ISLNK(buf.st_mode)) {
      /* check what it points to */
      xstat(entry, &buf);
      if (S_ISREG(buf.st_mode)) {
        struct DirListEntry * p = xmalloc(sizeof(struct DirListEntry));
        p->name = entry_wrt_root;
        p->next = head;
        head = p;
      }
      else {
        fatal("refusing to follow symbolic link: %s", entry);
      }
    }
#endif
    else {
      fatal("unknown file type: %s", entry);
    }
    free(entry);
  }
  closedir(dir);
  free(directory);
  return head;
}

struct DirListEntry * make_recursive_dir_list(const char * directory) {
  return recursive_dir_list(directory, NULL, NULL);
}

void free_dir_list(struct DirListEntry * list) {
  while (list != NULL) {
    struct DirListEntry * next = list->next;
    free(list->name);
    free(list);
    list = next;
  }
}

#ifndef HAVE_STRNDUP
char * strndup(const char * s, size_t size) {
  size_t length = strlen(s);
  if (length > size) {
    char * result = xmalloc(size + 1);
    strncpy(result, s, size);
    result[size] = '\0';
    return result;
  }
  else {
    char * result = xmalloc(length + 1);
    strcpy(result, s);
    return result;
  }
}
#endif

#ifndef HAVE_VASPRINTF
int vasprintf(char ** s, const char * template, va_list a) {
  int size = 100;
  *s = malloc(size);
  if (*s == NULL) {
    return -1;
  }

  va_list copy;
  va_copy(copy, a);
  int result = vsnprintf(*s, size, template, copy);
  if (result >= size) {
    int new_size = result;
    if (new_size == INT_MAX) {
      free(*s);
      return -1;
    }
    new_size++;
    char * new_s = realloc(*s, new_size);
    if (new_s == NULL) {
      free(*s);
      return -1;
    }
    *s = new_s;
    size = new_size;
    va_copy(copy, a);
    result = vsnprintf(*s, size, template, copy);
    assert(result == size - 1);
  }
  else if (result == -1) {
    while (result == -1) {
      if (size == INT_MAX) {
        free(*s);
        return -1;
      }
      int new_size;
      if (size > INT_MAX / 2) {
        new_size = INT_MAX;
      }
      else {
        new_size = 2 * size;
      }
      char * new_s = realloc(*s, new_size);
      if (new_s == NULL) {
        free(*s);
        return -1;
      }
      *s = new_s;
      size = new_size;
      va_copy(copy, a);
      result = vsnprintf(*s, size, template, copy);
    }
    assert(result <= size - 1);
  }

  return result;
}
#endif

#ifndef HAVE_ASPRINTF
int asprintf(char ** s, const char * template, ...) {
  va_list a;
  va_start(a, template);
  int result = vasprintf(s, template, a);
  va_end(a);
  return result;
}
#endif
1	/*
2	util.c - general purpose utility routines
3	Copyright (C) 2007, 2008 siliconforks.com
4
5	This program is free software; you can redistribute it and/or modify
6	it under the terms of the GNU General Public License as published by
7	the Free Software Foundation; either version 2 of the License, or
8	(at your option) any later version.
9
10	This program is distributed in the hope that it will be useful,
11	but WITHOUT ANY WARRANTY; without even the implied warranty of
12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13	GNU General Public License for more details.
14
15	You should have received a copy of the GNU General Public License along
16	with this program; if not, write to the Free Software Foundation, Inc.,
17	51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18	*/
19
20	#define _GNU_SOURCE
21
22	#include <config.h>
23
24	#include "util.h"
25
26	#include <assert.h>
27	#include <errno.h>
28	#include <limits.h>
29	#include <stdarg.h>
30	#include <stdio.h>
31	#include <stdint.h>
32	#include <string.h>
33	#include <strings.h>
34
35	#include <dirent.h>
36	#include <libgen.h>
37	#include <sys/stat.h>
38	#include <sys/types.h>
39	#include <unistd.h>
40
41	const char * program = NULL;
42
43	void fatal(const char * format, ...) {
44	fprintf(stderr, "%s: ", program);
45	va_list ap;
46	va_start(ap, format);
47	vfprintf(stderr, format, ap);
48	va_end(ap);
49	fputc('\n', stderr);
50	exit(EXIT_FAILURE);
51	}
52
53	void fatal_command_line(const char * format, ...) {
54	fprintf(stderr, "%s: ", program);
55	va_list ap;
56	va_start(ap, format);
57	vfprintf(stderr, format, ap);
58	va_end(ap);
59	fputc('\n', stderr);
60	fprintf(stderr, "Try `%s --help' for more information.\n", program);
61	exit(EXIT_FAILURE);
62	}
63
64	void fatal_source(const char * source_file, unsigned int line_number, const char * format, ...) {
65	fprintf(stderr, "%s:%s:%u: ", program, source_file, line_number);
66	va_list ap;
67	va_start(ap, format);
68	vfprintf(stderr, format, ap);
69	va_end(ap);
70	fputc('\n', stderr);
71	exit(EXIT_FAILURE);
72	}
73
74	void version(void) {
75	printf("%s %s\n", program, VERSION);
76	printf("Character encoding support: ");
77	#if HAVE_ICONV
78	printf("iconv\n");
79	#elif HAVE_MULTIBYTETOWIDECHAR
80	printf("MultiByteToWideChar\n");
81	#else
82	printf("none\n");
83	#endif
84	exit(EXIT_SUCCESS);
85	}
86
87	size_t addst(size_t x, size_t y) {
88	if (SIZE_MAX - x < y) {
89	fatal("integer overflow");
90	}
91	return x + y;
92	}
93
94	size_t mulst(size_t x, size_t y) {
95	if (x == 0 \|\| y == 0) {
96	return 0;
97	}
98	if (SIZE_MAX / x < y) {
99	fatal("integer overflow");
100	}
101	return x * y;
102	}
103
104	void * xmalloc(size_t size) {
105	void * result = malloc(size);
106	if (result == NULL) {
107	fatal("out of memory");
108	}
109	return result;
110	}
111
112	void * xrealloc(void * p, size_t size) {
113	void * result = realloc(p, size);
114	if (result == NULL) {
115	fatal("out of memory");
116	}
117	return result;
118	}
119
120	char * xstrdup(const char * s) {
121	char * result = strdup(s);
122	if (result == NULL) {
123	fatal("out of memory");
124	}
125	return result;
126	}
127
128	char * xstrndup(const char * s, size_t size) {
129	char * result = strndup(s, size);
130	if (result == NULL) {
131	fatal("out of memory");
132	}
133	return result;
134	}
135
136	int xasprintf(char ** s, const char * template, ...) {
137	va_list a;
138	va_start(a, template);
139	int result = vasprintf(s, template, a);
140	va_end(a);
141	if (result < 0) {
142	fatal("out of memory");
143	}
144	return result;
145	}
146
147	char * xgetcwd(void) {
148	char * result = getcwd(NULL, 0);
149	if (result == NULL) {
150	fatal("out of memory");
151	}
152	return result;
153	}
154
155	FILE * xfopen(const char * file, const char * mode) {
156	FILE * result = fopen(file, mode);
157	if (result == NULL) {
158	fatal("cannot open file: %s", file);
159	}
160	return result;
161	}
162
163	DIR * xopendir(const char * directory) {
164	DIR * result = opendir(directory);
165	if (result == NULL) {
166	fatal("cannot open directory: %s", directory);
167	}
168	return result;
169	}
170
171	void xlstat(const char * file, struct stat * buf) {
172	#ifdef _WIN32
173	return xstat(file, buf);
174	#else
175	if (lstat(file, buf) == -1) {
176	fatal("cannot stat file: %s", file);
177	}
178	#endif
179	}
180
181	void xstat(const char * file, struct stat * buf) {
182	if (stat(file, buf) == -1) {
183	fatal("cannot stat file: %s", file);
184	}
185	}
186
187	void xmkdir(const char * directory) {
188	int result;
189	#ifdef _WIN32
190	result = mkdir(directory);
191	#else
192	result = mkdir(directory, 0755);
193	#endif
194	if (result == -1) {
195	fatal("cannot create directory: %s", directory);
196	}
197	}
198
199	void mkdir_if_necessary(const char * directory) {
200	struct stat buf;
201	if (stat(directory, &buf) == 0) {
202	if (! S_ISDIR(buf.st_mode)) {
203	fatal("not a directory: %s", directory);
204	}
205	}
206	else {
207	if (errno == ENOENT) {
208	xmkdir(directory);
209	}
210	else {
211	fatal("cannot stat directory: %s", directory);
212	}
213	}
214	}
215
216	void mkdirs(const char * directory) {
217	char * d = xmalloc(strlen(directory) + 1);
218	for (const char * p = directory; *p != '\0'; p++) {
219	if (*p == '/' && p > directory) {
220	strncpy(d, directory, p - directory);
221	d[p - directory] = '\0';
222	mkdir_if_necessary(d);
223	}
224	}
225	mkdir_if_necessary(directory);
226	free(d);
227	}
228
229	void xchdir(const char * directory) {
230	if (chdir(directory) == -1) {
231	fatal("cannot change directory: %s", directory);
232	}
233	}
234
235	bool str_starts_with(const char * string, const char * prefix) {
236	const char * string_ptr = string;
237	const char * prefix_ptr = prefix;
238	while (string_ptr != '\0' && prefix_ptr != '\0') {
239	if (string_ptr != prefix_ptr) {
240	return false;
241	}
242	string_ptr++;
243	prefix_ptr++;
244	}
245	if (string_ptr == '\0' && prefix_ptr != '\0') {
246	return false;
247	}
248	return true;
249	}
250
251	bool str_ends_with(const char * string, const char * suffix) {
252	size_t string_length = strlen(string);
253	size_t suffix_length = strlen(suffix);
254	if (string_length < suffix_length) {
255	return false;
256	}
257	return strcmp(string + string_length - suffix_length, suffix) == 0;
258	}
259
260	char * make_path(const char * parent, const char * relative_path) {
261	size_t parent_length = strlen(parent);
262	size_t relative_path_length = strlen(relative_path);
263	size_t result_length = addst(parent_length, relative_path_length);
264	result_length = addst(result_length, 2);
265	char * result = xmalloc(result_length);
266	strcpy(result, parent);
267	result[parent_length] = '/';
268	strcpy(result + parent_length + 1, relative_path);
269	return result;
270	}
271
272	char * make_canonical_path(const char * relative_path) {
273	char * original_directory = xgetcwd();
274	char * base = make_basename(relative_path);
275	char * dir = make_dirname(relative_path);
276
277	xchdir(dir);
278	char * canonical_dir = xgetcwd();
279	char * result = make_path(canonical_dir, base);
280
281	free(canonical_dir);
282	free(base);
283	free(dir);
284	xchdir(original_directory);
285	free(original_directory);
286
287	return result;
288	}
289
290	char * make_basename(const char * path) {
291	char * copy = xstrdup(path);
292	char * result = xstrdup(basename(copy));
293	free(copy);
294	return result;
295	}
296
297	char * make_dirname(const char * path) {
298	char * copy = xstrdup(path);
299	char * result = xstrdup(dirname(copy));
300	free(copy);
301	return result;
302	}
303
304	int is_same_file(const char * file1, const char * file2) {
305	#ifdef _WIN32
306	#define FILECMP strcasecmp
307	#else
308	#define FILECMP strcmp
309	#endif
310	if (FILECMP(file1, file2) == 0) {
311	return 1;
312	}
313
314	char * canonical1 = make_canonical_path(file1);
315	char * canonical2 = make_canonical_path(file2);
316	int cmp = FILECMP(canonical1, canonical2);
317	free(canonical1);
318	free(canonical2);
319	if (cmp == 0) {
320	return 1;
321	}
322
323	#ifndef _WIN32
324	struct stat buf1;
325	if (stat(file1, &buf1) == -1) {
326	if (errno == ENOENT) {
327	return 0;
328	}
329	else {
330	fatal("cannot stat file: %s", file1);
331	}
332	}
333	struct stat buf2;
334	if (stat(file2, &buf2) == -1) {
335	if (errno == ENOENT) {
336	return 0;
337	}
338	else {
339	fatal("cannot stat file: %s", file2);
340	}
341	}
342	if (buf1.st_dev == buf2.st_dev &&
343	buf1.st_ino == buf2.st_ino) {
344	return 1;
345	}
346	#endif
347	return 0;
348	#undef FILECMP
349	}
350
351	int contains_file(const char * file1, const char * file2) {
352	int result = 0;
353	char * ancestor = make_canonical_path(file1);
354	char * d = make_canonical_path(file2);
355	char * parent = make_dirname(d);
356	while (strcmp(d, parent) != 0) {
357	if (is_same_file(ancestor, parent)) {
358	result = 1;
359	break;
360	}
361	free(d);
362	d = parent;
363	parent = make_dirname(d);
364	}
365	free(d);
366	free(parent);
367	free(ancestor);
368	return result;
369	}
370
371	void copy_stream(FILE * source, FILE * destination) {
372	unsigned char buffer[8192];
373	for (;;) {
374	int bytes_read = fread(buffer, 1, sizeof(buffer), source);
375	if (bytes_read == 0) {
376	break;
377	}
378	fwrite(buffer, 1, bytes_read, destination);
379	}
380	}
381
382	void copy_file(const char * source_file, const char * destination_file) {
383	FILE * source = xfopen(source_file, "rb");
384	FILE * destination = xfopen(destination_file, "wb");
385
386	copy_stream(source, destination);
387
388	#ifndef _WIN32
389	/* copy permissions */
390	struct stat buf;
391	if (fstat(fileno(source), &buf) == -1) {
392	fatal("cannot stat file: %s", source_file);
393	}
394	fchmod(fileno(destination), buf.st_mode);
395	#endif
396
397	fclose(source);
398	fclose(destination);
399	}
400
401	bool directory_is_empty(const char * directory) {
402	bool result = true;
403	DIR * dir = xopendir(directory);
404	struct dirent * e;
405	while ((e = readdir(dir)) != NULL) {
406	if (strcmp(e->d_name, ".") != 0 &&
407	strcmp(e->d_name, "..") != 0) {
408	result = false;
409	break;
410	}
411	}
412	closedir(dir);
413	return result;
414	}
415
416	static struct DirListEntry * recursive_dir_list(const char * root, const char * directory_wrt_root, struct DirListEntry * head) {
417	char * directory = directory_wrt_root == NULL? xstrdup(root): make_path(root, directory_wrt_root);
418	DIR * dir = xopendir(directory);
419	struct dirent * e;
420	while ((e = readdir(dir)) != NULL) {
421	if (strcmp(e->d_name, ".") == 0 \|\|
422	strcmp(e->d_name, "..") == 0) {
423	continue;
424	}
425	char * entry = make_path(directory, e->d_name);
426	char * entry_wrt_root = directory_wrt_root == NULL? xstrdup(e->d_name): make_path(directory_wrt_root, e->d_name);
427	struct stat buf;
428	xlstat(entry, &buf);
429	if (S_ISREG(buf.st_mode)) {
430	struct DirListEntry * p = xmalloc(sizeof(struct DirListEntry));
431	p->name = entry_wrt_root;
432	p->next = head;
433	head = p;
434	}
435	else if (S_ISDIR(buf.st_mode)) {
436	head = recursive_dir_list(root, entry_wrt_root, head);
437	free(entry_wrt_root);
438	}
439	#ifndef _WIN32
440	else if (S_ISLNK(buf.st_mode)) {
441	/* check what it points to */
442	xstat(entry, &buf);
443	if (S_ISREG(buf.st_mode)) {
444	struct DirListEntry * p = xmalloc(sizeof(struct DirListEntry));
445	p->name = entry_wrt_root;
446	p->next = head;
447	head = p;
448	}
449	else {
450	fatal("refusing to follow symbolic link: %s", entry);
451	}
452	}
453	#endif
454	else {
455	fatal("unknown file type: %s", entry);
456	}
457	free(entry);
458	}
459	closedir(dir);
460	free(directory);
461	return head;
462	}
463
464	struct DirListEntry * make_recursive_dir_list(const char * directory) {
465	return recursive_dir_list(directory, NULL, NULL);
466	}
467
468	void free_dir_list(struct DirListEntry * list) {
469	while (list != NULL) {
470	struct DirListEntry * next = list->next;
471	free(list->name);
472	free(list);
473	list = next;
474	}
475	}
476
477	#ifndef HAVE_STRNDUP
478	char * strndup(const char * s, size_t size) {
479	size_t length = strlen(s);
480	if (length > size) {
481	char * result = xmalloc(size + 1);
482	strncpy(result, s, size);
483	result[size] = '\0';
484	return result;
485	}
486	else {
487	char * result = xmalloc(length + 1);
488	strcpy(result, s);
489	return result;
490	}
491	}
492	#endif
493
494	#ifndef HAVE_VASPRINTF
495	int vasprintf(char ** s, const char * template, va_list a) {
496	int size = 100;
497	*s = malloc(size);
498	if (*s == NULL) {
499	return -1;
500	}
501
502	va_list copy;
503	va_copy(copy, a);
504	int result = vsnprintf(*s, size, template, copy);
505	if (result >= size) {
506	int new_size = result;
507	if (new_size == INT_MAX) {
508	free(*s);
509	return -1;
510	}
511	new_size++;
512	char * new_s = realloc(*s, new_size);
513	if (new_s == NULL) {
514	free(*s);
515	return -1;
516	}
517	*s = new_s;
518	size = new_size;
519	va_copy(copy, a);
520	result = vsnprintf(*s, size, template, copy);
521	assert(result == size - 1);
522	}
523	else if (result == -1) {
524	while (result == -1) {
525	if (size == INT_MAX) {
526	free(*s);
527	return -1;
528	}
529	int new_size;
530	if (size > INT_MAX / 2) {
531	new_size = INT_MAX;
532	}
533	else {
534	new_size = 2 * size;
535	}
536	char * new_s = realloc(*s, new_size);
537	if (new_s == NULL) {
538	free(*s);
539	return -1;
540	}
541	*s = new_s;
542	size = new_size;
543	va_copy(copy, a);
544	result = vsnprintf(*s, size, template, copy);
545	}
546	assert(result <= size - 1);
547	}
548
549	return result;
550	}
551	#endif
552
553	#ifndef HAVE_ASPRINTF
554	int asprintf(char ** s, const char * template, ...) {
555	va_list a;
556	va_start(a, template);
557	int result = vasprintf(s, template, a);
558	va_end(a);
559	return result;
560	}
561	#endif