summaryrefslogtreecommitdiff
path: root/source4/lib/util/util_file.c
blob: df4cb902f0bf9b8c95d9de5cbe88e308ba1a2784 (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
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
/*
 * Unix SMB/CIFS implementation.
 * SMB parameters and setup
 * Copyright (C) Andrew Tridgell 1992-1998 Modified by Jeremy Allison 1995.
 *
 * Added afdgets() Jelmer Vernooij 2005
 * 
 * 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 3 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., 675
 * Mass Ave, Cambridge, MA 02139, USA.
 */

#include "includes.h"
#include "system/shmem.h"
#include "system/filesys.h"

/**
 * @file
 * @brief File-related utility functions
 */

/**
read a line from a file with possible \ continuation chars. 
Blanks at the start or end of a line are stripped.
The string will be allocated if s2 is NULL
**/
_PUBLIC_ char *fgets_slash(char *s2,int maxlen,XFILE *f)
{
  char *s=s2;
  int len = 0;
  int c;
  BOOL start_of_line = True;

  if (x_feof(f))
    return(NULL);

  if (maxlen <2) return(NULL);

  if (!s2)
    {
      maxlen = MIN(maxlen,8);
      s = (char *)malloc(maxlen);
    }

  if (!s) return(NULL);

  *s = 0;

  while (len < maxlen-1)
    {
      c = x_getc(f);
      switch (c)
	{
	case '\r':
	  break;
	case '\n':
	  while (len > 0 && s[len-1] == ' ')
	    {
	      s[--len] = 0;
	    }
	  if (len > 0 && s[len-1] == '\\')
	    {
	      s[--len] = 0;
	      start_of_line = True;
	      break;
	    }
	  return(s);
	case EOF:
	  if (len <= 0 && !s2) 
	    SAFE_FREE(s);
	  return(len>0?s:NULL);
	case ' ':
	  if (start_of_line)
	    break;
	  /* fall through */
	default:
	  start_of_line = False;
	  s[len++] = c;
	  s[len] = 0;
	}
      if (!s2 && len > maxlen-3)
	{
	  char *t;
	  
	  maxlen *= 2;
	  t = realloc_p(s, char, maxlen);
	  if (!t) {
	    DEBUG(0,("fgets_slash: failed to expand buffer!\n"));
	    SAFE_FREE(s);
	    return(NULL);
	  } else s = t;
	}
    }
  return(s);
}

/**
 * Read one line (data until next newline or eof) and allocate it 
 */
_PUBLIC_ char *afdgets(int fd, TALLOC_CTX *mem_ctx, size_t hint)
{
	char *data = NULL;
	ssize_t alloc_size = 0, offset = 0, ret;
	int p;

	if (hint <= 0) hint = 0x100;

	do {
		alloc_size += hint;

		data = talloc_realloc(mem_ctx, data, char, alloc_size);

		if (!data)
			return NULL;

		ret = read(fd, data + offset, hint);

		if (ret == 0) {
			return NULL;
		}

		if (ret == -1) {
			talloc_free(data);
			return NULL;
		}

		/* Find newline */
		for (p = 0; p < ret; p++) {
			if (data[offset + p] == '\n')
				break;
		}

		if (p < ret) {
			data[offset + p] = '\0';

			/* Go back to position of newline */
			lseek(fd, p - ret + 1, SEEK_CUR);
			return data;
		}

		offset += ret;

	} while (ret == hint);

	data[offset] = '\0';

	return data;
}


/**
load a file into memory from a fd.
**/
_PUBLIC_ char *fd_load(int fd, size_t *size, TALLOC_CTX *mem_ctx)
{
	struct stat sbuf;
	char *p;

	if (fstat(fd, &sbuf) != 0) return NULL;

	p = (char *)talloc_size(mem_ctx, sbuf.st_size+1);
	if (!p) return NULL;

	if (read(fd, p, sbuf.st_size) != sbuf.st_size) {
		talloc_free(p);
		return NULL;
	}
	p[sbuf.st_size] = 0;

	if (size) *size = sbuf.st_size;

	return p;
}

/**
load a file into memory
**/
_PUBLIC_ char *file_load(const char *fname, size_t *size, TALLOC_CTX *mem_ctx)
{
	int fd;
	char *p;

	if (!fname || !*fname) return NULL;
	
	fd = open(fname,O_RDONLY);
	if (fd == -1) return NULL;

	p = fd_load(fd, size, mem_ctx);

	close(fd);

	return p;
}


/**
mmap (if possible) or read a file
**/
_PUBLIC_ void *map_file(const char *fname, size_t size)
{
	size_t s2 = 0;
	void *p = NULL;
#ifdef HAVE_MMAP
	int fd;
	fd = open(fname, O_RDONLY, 0);
	if (fd == -1) {
		DEBUG(2,("Failed to load %s - %s\n", fname, strerror(errno)));
		return NULL;
	}
	p = mmap(NULL, size, PROT_READ, MAP_SHARED|MAP_FILE, fd, 0);
	close(fd);
	if (p == MAP_FAILED) {
		DEBUG(1,("Failed to mmap %s - %s\n", fname, strerror(errno)));
		return NULL;
	}
#endif
	if (!p) {
		p = file_load(fname, &s2, talloc_autofree_context());
		if (!p) return NULL;
		if (s2 != size) {
			DEBUG(1,("incorrect size for %s - got %d expected %d\n",
				 fname, (int)s2, (int)size));
			talloc_free(p);
			return NULL;
		}
	}

	return p;
}


/**
parse a buffer into lines
'p' will be freed on error, and otherwise will be made a child of the returned array
**/
static char **file_lines_parse(char *p, size_t size, int *numlines, TALLOC_CTX *mem_ctx)
{
	int i;
	char *s, **ret;

	if (!p) return NULL;

	for (s = p, i=0; s < p+size; s++) {
		if (s[0] == '\n') i++;
	}

	ret = talloc_array(mem_ctx, char *, i+2);
	if (!ret) {
		talloc_free(p);
		return NULL;
	}	
	
	talloc_steal(ret, p);
	
	memset(ret, 0, sizeof(ret[0])*(i+2));

	ret[0] = p;
	for (s = p, i=0; s < p+size; s++) {
		if (s[0] == '\n') {
			s[0] = 0;
			i++;
			ret[i] = s+1;
		}
		if (s[0] == '\r') s[0] = 0;
	}

	/* remove any blank lines at the end */
	while (i > 0 && ret[i-1][0] == 0) {
		i--;
	}

	if (numlines) *numlines = i;

	return ret;
}


/**
load a file into memory and return an array of pointers to lines in the file
must be freed with talloc_free(). 
**/
_PUBLIC_ char **file_lines_load(const char *fname, int *numlines, TALLOC_CTX *mem_ctx)
{
	char *p;
	size_t size;

	p = file_load(fname, &size, mem_ctx);
	if (!p) return NULL;

	return file_lines_parse(p, size, numlines, mem_ctx);
}

/**
load a fd into memory and return an array of pointers to lines in the file
must be freed with talloc_free(). If convert is true calls unix_to_dos on
the list.
**/
_PUBLIC_ char **fd_lines_load(int fd, int *numlines, TALLOC_CTX *mem_ctx)
{
	char *p;
	size_t size;

	p = fd_load(fd, &size, mem_ctx);
	if (!p) return NULL;

	return file_lines_parse(p, size, numlines, mem_ctx);
}


/**
take a list of lines and modify them to produce a list where \ continues
a line
**/
_PUBLIC_ void file_lines_slashcont(char **lines)
{
	int i, j;

	for (i=0; lines[i];) {
		int len = strlen(lines[i]);
		if (lines[i][len-1] == '\\') {
			lines[i][len-1] = ' ';
			if (lines[i+1]) {
				char *p = &lines[i][len];
				while (p < lines[i+1]) *p++ = ' ';
				for (j = i+1; lines[j]; j++) lines[j] = lines[j+1];
			}
		} else {
			i++;
		}
	}
}

/**
  save a lump of data into a file. Mostly used for debugging 
*/
_PUBLIC_ BOOL file_save(const char *fname, const void *packet, size_t length)
{
	int fd;
	fd = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0644);
	if (fd == -1) {
		return False;
	}
	if (write(fd, packet, length) != (size_t)length) {
		return False;
	}
	close(fd);
	return True;
}

_PUBLIC_ int vfdprintf(int fd, const char *format, va_list ap) _PRINTF_ATTRIBUTE(2,0)
{
	char *p;
	int len, ret;
	va_list ap2;

	va_copy(ap2, ap);
	len = vasprintf(&p, format, ap2);
	va_end(ap2);
	if (len <= 0) return len;
	ret = write(fd, p, len);
	SAFE_FREE(p);
	return ret;
}

_PUBLIC_ int fdprintf(int fd, const char *format, ...) _PRINTF_ATTRIBUTE(2,3)
{
	va_list ap;
	int ret;

	va_start(ap, format);
	ret = vfdprintf(fd, format, ap);
	va_end(ap);
	return ret;
}


/*
  try to determine if the filesystem supports large files
*/
_PUBLIC_ bool large_file_support(const char *path)
{
	int fd;
	ssize_t ret;
	char c;

	fd = open(path, O_RDWR|O_CREAT, 0600);
	unlink(path);
	if (fd == -1) {
		/* have to assume large files are OK */
		return true;
	}
	ret = pread(fd, &c, 1, ((uint64_t)1)<<32);
	close(fd);
	return ret == 0;
}