openpam_readlinev.c revision 236099 
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 *    in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote
15 *    products derived from this software without specific prior written
16 *    permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * $Id: openpam_readlinev.c 588 2012-04-08 11:52:25Z des $
31 */
32
33#ifdef HAVE_CONFIG_H
34# include "config.h"
35#endif
36
37#include <errno.h>
38#include <stdio.h>
39#include <stdlib.h>
40
41#include <security/pam_appl.h>
42
43#include "openpam_impl.h"
44
45#define MIN_WORDV_SIZE	32
46
47/*
48 * OpenPAM extension
49 *
50 * Read a line from a file and split it into words.
51 */
52
53char **
54openpam_readlinev(FILE *f, int *lineno, int *lenp)
55{
56	char *word, **wordv, **tmp;
57	size_t wordlen, wordvsize;
58	int ch, serrno, wordvlen;
59
60	wordvsize = MIN_WORDV_SIZE;
61	wordvlen = 0;
62	if ((wordv = malloc(wordvsize * sizeof *wordv)) == NULL) {
63		openpam_log(PAM_LOG_ERROR, "malloc(): %m");
64		errno = ENOMEM;
65		return (NULL);
66	}
67	wordv[wordvlen] = NULL;
68	while ((word = openpam_readword(f, lineno, &wordlen)) != NULL) {
69		if ((unsigned int)wordvlen + 1 >= wordvsize) {
70			/* need to expand the array */
71			wordvsize *= 2;
72			tmp = realloc(wordv, wordvsize * sizeof *wordv);
73			if (tmp == NULL) {
74				openpam_log(PAM_LOG_ERROR, "malloc(): %m");
75				errno = ENOMEM;
76				break;
77			}
78			wordv = tmp;
79		}
80		/* insert our word */
81		wordv[wordvlen++] = word;
82		wordv[wordvlen] = NULL;
83	}
84	if (errno != 0) {
85		/* I/O error or out of memory */
86		serrno = errno;
87		while (wordvlen--)
88			free(wordv[wordvlen]);
89		free(wordv);
90		errno = serrno;
91		return (NULL);
92	}
93	/* assert(!ferror(f)) */
94	ch = fgetc(f);
95	/* assert(ch == EOF || ch == '\n') */
96	if (ch == EOF && wordvlen == 0) {
97		free(wordv);
98		return (NULL);
99	}
100	if (ch == '\n' && lineno != NULL)
101		++*lineno;
102	if (lenp != NULL)
103		*lenp = wordvlen;
104	return (wordv);
105}
106
107/**
108 * The =openpam_readlinev function reads a line from a file, splits it
109 * into words according to the rules described in the =openpam_readword
110 * manual page, and returns a list of those words.
111 *
112 * If =lineno is not =NULL, the integer variable it points to is
113 * incremented every time a newline character is read.
114 * This includes quoted or escaped newline characters and the newline
115 * character at the end of the line.
116 *
117 * If =lenp is not =NULL, the number of words on the line is stored in the
118 * variable to which it points.
119 *
120 * RETURN VALUES
121 *
122 * If successful, the =openpam_readlinev function returns a pointer to a
123 * dynamically allocated array of pointers to individual dynamically
124 * allocated NUL-terminated strings, each containing a single word, in the
125 * order in which they were encountered on the line.
126 * The array is terminated by a =NULL pointer.
127 *
128 * The caller is responsible for freeing both the array and the individual
129 * strings by passing each of them to =!free.
130 *
131 * If the end of the line was reached before any words were read,
132 * =openpam_readlinev returns a pointer to a dynamically allocated array
133 * containing a single =NULL pointer.
134 *
135 * The =openpam_readlinev function can fail and return =NULL for one of
136 * four reasons:
137 *
138 *  - The end of the file was reached before any words were read; :errno is
139 *    zero, =!ferror returns zero, and =!feof returns a non-zero value.
140 *
141 *  - The end of the file was reached while a quote or backslash escape
142 *    was in effect; :errno is set to =EINVAL, =!ferror returns zero, and
143 *    =!feof returns a non-zero value.
144 *
145 *  - An error occurred while reading from the file; :errno is non-zero,
146 *    =!ferror returns a non-zero value and =!feof returns zero.
147 *
148 *  - A =!malloc or =!realloc call failed; :errno is set to =ENOMEM,
149 *    =!ferror returns a non-zero value, and =!feof may or may not return
150 *    a non-zero value.
151 *
152 * >openpam_readline
153 * >openpam_readword
154 *
155 * AUTHOR DES
156 */
157