samba-mirror/source3/lib/util_file.c

/*
 * Unix SMB/CIFS implementation.
 * SMB parameters and setup
 * Copyright (C) Andrew Tridgell 1992-1998 Modified by Jeremy Allison 1995.
 * 
 * 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, see <http://www.gnu.org/licenses/>.
 */

#include "includes.h"

#ifndef MAP_FAILED
#define MAP_FAILED ((void *)-1)
#endif

/****************************************************************************
 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.
****************************************************************************/

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 *)SMB_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;
				}
			default:
				start_of_line = False;
				s[len++] = c;
				s[len] = 0;
		}

		if (!s2 && len > maxlen-3) {
			maxlen *= 2;
			s = (char *)SMB_REALLOC(s,maxlen);
			if (!s) {
				DEBUG(0,("fgets_slash: failed to expand buffer!\n"));
				return(NULL);
			}
		}
	}
	return(s);
}

/****************************************************************************
 Load from a pipe into memory.
****************************************************************************/

static char *file_pload(char *syscmd, size_t *size)
{
	int fd, n;
	char *p;
	char buf[1024];
	size_t total;

	fd = sys_popen(syscmd);
	if (fd == -1) {
		return NULL;
	}

	p = NULL;
	total = 0;

	while ((n = read(fd, buf, sizeof(buf))) > 0) {
		p = (char *)SMB_REALLOC(p, total + n + 1);
		if (!p) {
		        DEBUG(0,("file_pload: failed to expand buffer!\n"));
			close(fd);
			return NULL;
		}
		memcpy(p+total, buf, n);
		total += n;
	}

	if (p) {
		p[total] = 0;
	}

	/* FIXME: Perhaps ought to check that the command completed
	 * successfully (returned 0); if not the data may be
	 * truncated. */
	sys_pclose(fd);

	if (size) {
		*size = total;
	}

	return p;
}

/****************************************************************************
 Load a file into memory from a fd.
 Truncate at maxsize. If maxsize == 0 - no limit.
****************************************************************************/ 

char *fd_load(int fd, size_t *psize, size_t maxsize)
{
	SMB_STRUCT_STAT sbuf;
	size_t size;
	char *p;

	if (sys_fstat(fd, &sbuf) != 0) {
		return NULL;
	}

	size = sbuf.st_size;
	if (maxsize) {
		size = MIN(size, maxsize);
	}

	p = (char *)SMB_MALLOC(size+1);
	if (!p) {
		return NULL;
	}

	if (read(fd, p, size) != size) {
		SAFE_FREE(p);
		return NULL;
	}
	p[size] = 0;

	if (psize) {
		*psize = size;
	}

	return p;
}

/****************************************************************************
 Load a file into memory.
****************************************************************************/

char *file_load(const char *fname, size_t *size, size_t maxsize)
{
	int fd;
	char *p;

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

	p = fd_load(fd, size, maxsize);
	close(fd);
	return p;
}

/*******************************************************************
 unmap or free memory
*******************************************************************/

bool unmap_file(void* start, size_t size)
{
#ifdef HAVE_MMAP
	if ( munmap( start, size ) != 0 ) {
		DEBUG( 1, ("map_file: Failed to unmap address %p "
			"of size %u - %s\n", 
			start, (unsigned int)size, strerror(errno) ));
		return False;
	}
	return True;
#else
	SAFE_FREE( start );
	return True;
#endif
}

/*******************************************************************
 mmap (if possible) or read a file.
********************************************************************/

void *map_file(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,("map_file: 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,("map_file: Failed to mmap %s - %s\n", fname, strerror(errno)));
		return NULL;
	}
#endif
	if (!p) {
		p = file_load(fname, &s2, 0);
		if (!p) {
			return NULL;
		}
		if (s2 != size) {
			DEBUG(1,("map_file: incorrect size for %s - got %lu expected %lu\n",
				 fname, (unsigned long)s2, (unsigned long)size));
			SAFE_FREE(p);	
			return NULL;
		}
	}
	return p;
}

/****************************************************************************
 Parse a buffer into lines.
****************************************************************************/

static char **file_lines_parse(char *p, size_t size, int *numlines)
{
	int i;
	char *s, **ret;

	if (!p) {
		return NULL;
	}

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

	ret = SMB_MALLOC_ARRAY(char *, i+2);
	if (!ret) {
		SAFE_FREE(p);
		return NULL;
	}	
	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 file_lines_free(). 
****************************************************************************/

char **file_lines_load(const char *fname, int *numlines, size_t maxsize)
{
	char *p;
	size_t size = 0;

	p = file_load(fname, &size, maxsize);
	if (!p) {
		return NULL;
	}

	return file_lines_parse(p, size, numlines);
}

/****************************************************************************
 Load a fd into memory and return an array of pointers to lines in the file
 must be freed with file_lines_free(). If convert is true calls unix_to_dos on
 the list.
****************************************************************************/

char **fd_lines_load(int fd, int *numlines, size_t maxsize)
{
	char *p;
	size_t size;

	p = fd_load(fd, &size, maxsize);
	if (!p) {
		return NULL;
	}

	return file_lines_parse(p, size, numlines);
}

/****************************************************************************
 Load a pipe into memory and return an array of pointers to lines in the data
 must be freed with file_lines_free(). 
****************************************************************************/

char **file_lines_pload(char *syscmd, int *numlines)
{
	char *p;
	size_t size;

	p = file_pload(syscmd, &size);
	if (!p) {
		return NULL;
	}

	return file_lines_parse(p, size, numlines);
}

/****************************************************************************
 Free lines loaded with file_lines_load.
****************************************************************************/

void file_lines_free(char **lines)
{
	if (!lines) {
		return;
	}
	SAFE_FREE(lines[0]);
	SAFE_FREE(lines);
}

/****************************************************************************
 Take a list of lines and modify them to produce a list where \ continues
 a line.
****************************************************************************/

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.
****************************************************************************/

bool file_save(const char *fname, 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;
}