openpam_readlinev.c revision 255376 
1/*-
2 * Copyright (c) 2012 Dag-Erling Sm��rgrav
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote
14 *    products derived from this software without specific prior written
15 *    permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $Id: openpam_readlinev.c 648 2013-03-05 17:54:27Z des $
30 */
31
32#ifdef HAVE_CONFIG_H
33# include "config.h"
34#endif
35
36#include <errno.h>
37#include <stdio.h>
38#include <stdlib.h>
39
40#include <security/pam_appl.h>
41
42#include "openpam_impl.h"
43
44#define MIN_WORDV_SIZE	32
45
46/*
47 * OpenPAM extension
48 *
49 * Read a line from a file and split it into words.
50 */
51
52char **
53openpam_readlinev(FILE *f, int *lineno, int *lenp)
54{
55	char *word, **wordv, **tmp;
56	size_t wordlen, wordvsize;
57	int ch, serrno, wordvlen;
58
59	wordvsize = MIN_WORDV_SIZE;
60	wordvlen = 0;
61	if ((wordv = malloc(wordvsize * sizeof *wordv)) == NULL) {
62		openpam_log(PAM_LOG_ERROR, "malloc(): %m");
63		errno = ENOMEM;
64		return (NULL);
65	}
66	wordv[wordvlen] = NULL;
67	while ((word = openpam_readword(f, lineno, &wordlen)) != NULL) {
68		if ((unsigned int)wordvlen + 1 >= wordvsize) {
69			/* need to expand the array */
70			wordvsize *= 2;
71			tmp = realloc(wordv, wordvsize * sizeof *wordv);
72			if (tmp == NULL) {
73				openpam_log(PAM_LOG_ERROR, "malloc(): %m");
74				errno = ENOMEM;
75				break;
76			}
77			wordv = tmp;
78		}
79		/* insert our word */
80		wordv[wordvlen++] = word;
81		wordv[wordvlen] = NULL;
82	}
83	if (errno != 0) {
84		/* I/O error or out of memory */
85		serrno = errno;
86		while (wordvlen--)
87			free(wordv[wordvlen]);
88		free(wordv);
89		errno = serrno;
90		return (NULL);
91	}
92	/* assert(!ferror(f)) */
93	ch = fgetc(f);
94	/* assert(ch == EOF || ch == '\n') */
95	if (ch == EOF && wordvlen == 0) {
96		free(wordv);
97		return (NULL);
98	}
99	if (ch == '\n' && lineno != NULL)
100		++*lineno;
101	if (lenp != NULL)
102		*lenp = wordvlen;
103	return (wordv);
104}
105
106/**
107 * The =openpam_readlinev function reads a line from a file, splits it
108 * into words according to the rules described in the =openpam_readword
109 * manual page, and returns a list of those words.
110 *
111 * If =lineno is not =NULL, the integer variable it points to is
112 * incremented every time a newline character is read.
113 * This includes quoted or escaped newline characters and the newline
114 * character at the end of the line.
115 *
116 * If =lenp is not =NULL, the number of words on the line is stored in the
117 * variable to which it points.
118 *
119 * RETURN VALUES
120 *
121 * If successful, the =openpam_readlinev function returns a pointer to a
122 * dynamically allocated array of pointers to individual dynamically
123 * allocated NUL-terminated strings, each containing a single word, in the
124 * order in which they were encountered on the line.
125 * The array is terminated by a =NULL pointer.
126 *
127 * The caller is responsible for freeing both the array and the individual
128 * strings by passing each of them to =!free.
129 *
130 * If the end of the line was reached before any words were read,
131 * =openpam_readlinev returns a pointer to a dynamically allocated array
132 * containing a single =NULL pointer.
133 *
134 * The =openpam_readlinev function can fail and return =NULL for one of
135 * four reasons:
136 *
137 *  - The end of the file was reached before any words were read; :errno is
138 *    zero, =!ferror returns zero, and =!feof returns a non-zero value.
139 *
140 *  - The end of the file was reached while a quote or backslash escape
141 *    was in effect; :errno is set to =EINVAL, =!ferror returns zero, and
142 *    =!feof returns a non-zero value.
143 *
144 *  - An error occurred while reading from the file; :errno is non-zero,
145 *    =!ferror returns a non-zero value and =!feof returns zero.
146 *
147 *  - A =!malloc or =!realloc call failed; :errno is set to =ENOMEM,
148 *    =!ferror returns a non-zero value, and =!feof may or may not return
149 *    a non-zero value.
150 *
151 * >openpam_readline
152 * >openpam_readword
153 *
154 * AUTHOR DES
155 */
156