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 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);
    }
    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);
      }
    }
    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 version(void) {
65	printf("%s %s\n", program, VERSION);
66	printf("Character encoding support: ");
67	#if HAVE_ICONV
68	printf("iconv\n");
69	#elif HAVE_MULTIBYTETOWIDECHAR
70	printf("MultiByteToWideChar\n");
71	#else
72	printf("none\n");
73	#endif
74	exit(EXIT_SUCCESS);
75	}
76
77	size_t addst(size_t x, size_t y) {
78	if (SIZE_MAX - x < y) {
79	fatal("integer overflow");
80	}
81	return x + y;
82	}
83
84	size_t mulst(size_t x, size_t y) {
85	if (x == 0 \|\| y == 0) {
86	return 0;
87	}
88	if (SIZE_MAX / x < y) {
89	fatal("integer overflow");
90	}
91	return x * y;
92	}
93
94	void * xmalloc(size_t size) {
95	void * result = malloc(size);
96	if (result == NULL) {
97	fatal("out of memory");
98	}
99	return result;
100	}
101
102	void * xrealloc(void * p, size_t size) {
103	void * result = realloc(p, size);
104	if (result == NULL) {
105	fatal("out of memory");
106	}
107	return result;
108	}
109
110	char * xstrdup(const char * s) {
111	char * result = strdup(s);
112	if (result == NULL) {
113	fatal("out of memory");
114	}
115	return result;
116	}
117
118	char * xstrndup(const char * s, size_t size) {
119	char * result = strndup(s, size);
120	if (result == NULL) {
121	fatal("out of memory");
122	}
123	return result;
124	}
125
126	int xasprintf(char ** s, const char * template, ...) {
127	va_list a;
128	va_start(a, template);
129	int result = vasprintf(s, template, a);
130	va_end(a);
131	if (result < 0) {
132	fatal("out of memory");
133	}
134	return result;
135	}
136
137	char * xgetcwd(void) {
138	char * result = getcwd(NULL, 0);
139	if (result == NULL) {
140	fatal("out of memory");
141	}
142	return result;
143	}
144
145	FILE * xfopen(const char * file, const char * mode) {
146	FILE * result = fopen(file, mode);
147	if (result == NULL) {
148	fatal("cannot open file: %s", file);
149	}
150	return result;
151	}
152
153	DIR * xopendir(const char * directory) {
154	DIR * result = opendir(directory);
155	if (result == NULL) {
156	fatal("cannot open directory: %s", directory);
157	}
158	return result;
159	}
160
161	void xlstat(const char * file, struct stat * buf) {
162	#ifdef _WIN32
163	return xstat(file, buf);
164	#else
165	if (lstat(file, buf) == -1) {
166	fatal("cannot stat file: %s", file);
167	}
168	#endif
169	}
170
171	void xstat(const char * file, struct stat * buf) {
172	if (stat(file, buf) == -1) {
173	fatal("cannot stat file: %s", file);
174	}
175	}
176
177	void xmkdir(const char * directory) {
178	int result;
179	#ifdef _WIN32
180	result = mkdir(directory);
181	#else
182	result = mkdir(directory, 0755);
183	#endif
184	if (result == -1) {
185	fatal("cannot create directory: %s", directory);
186	}
187	}
188
189	void mkdir_if_necessary(const char * directory) {
190	struct stat buf;
191	if (stat(directory, &buf) == 0) {
192	if (! S_ISDIR(buf.st_mode)) {
193	fatal("not a directory: %s", directory);
194	}
195	}
196	else {
197	if (errno == ENOENT) {
198	xmkdir(directory);
199	}
200	else {
201	fatal("cannot stat directory: %s", directory);
202	}
203	}
204	}
205
206	void mkdirs(const char * directory) {
207	char * d = xmalloc(strlen(directory) + 1);
208	for (const char * p = directory; *p != '\0'; p++) {
209	if (*p == '/' && p > directory) {
210	strncpy(d, directory, p - directory);
211	d[p - directory] = '\0';
212	mkdir_if_necessary(d);
213	}
214	}
215	mkdir_if_necessary(directory);
216	free(d);
217	}
218
219	void xchdir(const char * directory) {
220	if (chdir(directory) == -1) {
221	fatal("cannot change directory: %s", directory);
222	}
223	}
224
225	bool str_starts_with(const char * string, const char * prefix) {
226	const char * string_ptr = string;
227	const char * prefix_ptr = prefix;
228	while (string_ptr != '\0' && prefix_ptr != '\0') {
229	if (string_ptr != prefix_ptr) {
230	return false;
231	}
232	string_ptr++;
233	prefix_ptr++;
234	}
235	if (string_ptr == '\0' && prefix_ptr != '\0') {
236	return false;
237	}
238	return true;
239	}
240
241	bool str_ends_with(const char * string, const char * suffix) {
242	size_t string_length = strlen(string);
243	size_t suffix_length = strlen(suffix);
244	if (string_length < suffix_length) {
245	return false;
246	}
247	return strcmp(string + string_length - suffix_length, suffix) == 0;
248	}
249
250	char * make_path(const char * parent, const char * relative_path) {
251	size_t parent_length = strlen(parent);
252	size_t relative_path_length = strlen(relative_path);
253	size_t result_length = addst(parent_length, relative_path_length);
254	result_length = addst(result_length, 2);
255	char * result = xmalloc(result_length);
256	strcpy(result, parent);
257	result[parent_length] = '/';
258	strcpy(result + parent_length + 1, relative_path);
259	return result;
260	}
261
262	char * make_canonical_path(const char * relative_path) {
263	char * original_directory = xgetcwd();
264	char * base = make_basename(relative_path);
265	char * dir = make_dirname(relative_path);
266
267	xchdir(dir);
268	char * canonical_dir = xgetcwd();
269	char * result = make_path(canonical_dir, base);
270
271	free(canonical_dir);
272	free(base);
273	free(dir);
274	xchdir(original_directory);
275	free(original_directory);
276
277	return result;
278	}
279
280	char * make_basename(const char * path) {
281	char * copy = xstrdup(path);
282	char * result = xstrdup(basename(copy));
283	free(copy);
284	return result;
285	}
286
287	char * make_dirname(const char * path) {
288	char * copy = xstrdup(path);
289	char * result = xstrdup(dirname(copy));
290	free(copy);
291	return result;
292	}
293
294	int is_same_file(const char * file1, const char * file2) {
295	#ifdef _WIN32
296	#define FILECMP strcasecmp
297	#else
298	#define FILECMP strcmp
299	#endif
300	if (FILECMP(file1, file2) == 0) {
301	return 1;
302	}
303
304	char * canonical1 = make_canonical_path(file1);
305	char * canonical2 = make_canonical_path(file2);
306	int cmp = FILECMP(canonical1, canonical2);
307	free(canonical1);
308	free(canonical2);
309	if (cmp == 0) {
310	return 1;
311	}
312
313	#ifndef _WIN32
314	struct stat buf1;
315	if (stat(file1, &buf1) == -1) {
316	if (errno == ENOENT) {
317	return 0;
318	}
319	else {
320	fatal("cannot stat file: %s", file1);
321	}
322	}
323	struct stat buf2;
324	if (stat(file2, &buf2) == -1) {
325	if (errno == ENOENT) {
326	return 0;
327	}
328	else {
329	fatal("cannot stat file: %s", file2);
330	}
331	}
332	if (buf1.st_dev == buf2.st_dev &&
333	buf1.st_ino == buf2.st_ino) {
334	return 1;
335	}
336	#endif
337	return 0;
338	#undef FILECMP
339	}
340
341	int contains_file(const char * file1, const char * file2) {
342	int result = 0;
343	char * ancestor = make_canonical_path(file1);
344	char * d = make_canonical_path(file2);
345	char * parent = make_dirname(d);
346	while (strcmp(d, parent) != 0) {
347	if (is_same_file(ancestor, parent)) {
348	result = 1;
349	break;
350	}
351	free(d);
352	d = parent;
353	parent = make_dirname(d);
354	}
355	free(d);
356	free(parent);
357	free(ancestor);
358	return result;
359	}
360
361	void copy_stream(FILE * source, FILE * destination) {
362	unsigned char buffer[8192];
363	for (;;) {
364	int bytes_read = fread(buffer, 1, sizeof(buffer), source);
365	if (bytes_read == 0) {
366	break;
367	}
368	fwrite(buffer, 1, bytes_read, destination);
369	}
370	}
371
372	void copy_file(const char * source_file, const char * destination_file) {
373	FILE * source = xfopen(source_file, "rb");
374	FILE * destination = xfopen(destination_file, "wb");
375
376	copy_stream(source, destination);
377
378	#ifndef _WIN32
379	/* copy permissions */
380	struct stat buf;
381	if (fstat(fileno(source), &buf) == -1) {
382	fatal("cannot stat file: %s", source_file);
383	}
384	fchmod(fileno(destination), buf.st_mode);
385	#endif
386
387	fclose(source);
388	fclose(destination);
389	}
390
391	bool directory_is_empty(const char * directory) {
392	bool result = true;
393	DIR * dir = xopendir(directory);
394	struct dirent * e;
395	while ((e = readdir(dir)) != NULL) {
396	if (strcmp(e->d_name, ".") != 0 &&
397	strcmp(e->d_name, "..") != 0) {
398	result = false;
399	break;
400	}
401	}
402	closedir(dir);
403	return result;
404	}
405
406	static struct DirListEntry * recursive_dir_list(const char * root, const char * directory_wrt_root, struct DirListEntry * head) {
407	char * directory = directory_wrt_root == NULL? xstrdup(root): make_path(root, directory_wrt_root);
408	DIR * dir = xopendir(directory);
409	struct dirent * e;
410	while ((e = readdir(dir)) != NULL) {
411	if (strcmp(e->d_name, ".") == 0 \|\|
412	strcmp(e->d_name, "..") == 0) {
413	continue;
414	}
415	char * entry = make_path(directory, e->d_name);
416	char * entry_wrt_root = directory_wrt_root == NULL? xstrdup(e->d_name): make_path(directory_wrt_root, e->d_name);
417	struct stat buf;
418	xlstat(entry, &buf);
419	if (S_ISREG(buf.st_mode)) {
420	struct DirListEntry * p = xmalloc(sizeof(struct DirListEntry));
421	p->name = entry_wrt_root;
422	p->next = head;
423	head = p;
424	}
425	else if (S_ISDIR(buf.st_mode)) {
426	head = recursive_dir_list(root, entry_wrt_root, head);
427	free(entry_wrt_root);
428	}
429	else if (S_ISLNK(buf.st_mode)) {
430	/* check what it points to */
431	xstat(entry, &buf);
432	if (S_ISREG(buf.st_mode)) {
433	struct DirListEntry * p = xmalloc(sizeof(struct DirListEntry));
434	p->name = entry_wrt_root;
435	p->next = head;
436	head = p;
437	}
438	else {
439	fatal("refusing to follow symbolic link: %s", entry);
440	}
441	}
442	else {
443	fatal("unknown file type: %s", entry);
444	}
445	free(entry);
446	}
447	closedir(dir);
448	free(directory);
449	return head;
450	}
451
452	struct DirListEntry * make_recursive_dir_list(const char * directory) {
453	return recursive_dir_list(directory, NULL, NULL);
454	}
455
456	void free_dir_list(struct DirListEntry * list) {
457	while (list != NULL) {
458	struct DirListEntry * next = list->next;
459	free(list->name);
460	free(list);
461	list = next;
462	}
463	}
464
465	#ifndef HAVE_STRNDUP
466	char * strndup(const char * s, size_t size) {
467	size_t length = strlen(s);
468	if (length > size) {
469	char * result = xmalloc(size + 1);
470	strncpy(result, s, size);
471	result[size] = '\0';
472	return result;
473	}
474	else {
475	char * result = xmalloc(length + 1);
476	strcpy(result, s);
477	return result;
478	}
479	}
480	#endif
481
482	#ifndef HAVE_VASPRINTF
483	int vasprintf(char ** s, const char * template, va_list a) {
484	int size = 100;
485	*s = malloc(size);
486	if (*s == NULL) {
487	return -1;
488	}
489
490	va_list copy;
491	va_copy(copy, a);
492	int result = vsnprintf(*s, size, template, copy);
493	if (result >= size) {
494	int new_size = result;
495	if (new_size == INT_MAX) {
496	free(*s);
497	return -1;
498	}
499	new_size++;
500	char * new_s = realloc(*s, new_size);
501	if (new_s == NULL) {
502	free(*s);
503	return -1;
504	}
505	*s = new_s;
506	size = new_size;
507	va_copy(copy, a);
508	result = vsnprintf(*s, size, template, copy);
509	assert(result == size - 1);
510	}
511	else if (result == -1) {
512	while (result == -1) {
513	if (size == INT_MAX) {
514	free(*s);
515	return -1;
516	}
517	int new_size;
518	if (size > INT_MAX / 2) {
519	new_size = INT_MAX;
520	}
521	else {
522	new_size = 2 * size;
523	}
524	char * new_s = realloc(*s, new_size);
525	if (new_s == NULL) {
526	free(*s);
527	return -1;
528	}
529	*s = new_s;
530	size = new_size;
531	va_copy(copy, a);
532	result = vsnprintf(*s, size, template, copy);
533	}
534	assert(result <= size - 1);
535	}
536
537	return result;
538	}
539	#endif
540
541	#ifndef HAVE_ASPRINTF
542	int asprintf(char ** s, const char * template, ...) {
543	va_list a;
544	va_start(a, template);
545	int result = vasprintf(s, template, a);
546	va_end(a);
547	return result;
548	}
549	#endif