1 /* -*- mode: C; c-basic-offset: 4; indent-tabs-mode: t -*- */
2 /*
3 * self_exec.c: self_exec magic required to run child functions on uClinux
4 *
5 * Copyright (C) 2005 Paul J.Y. Lahaie <pjlahaie-at-steamballoon.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20 *
21 * This software was produced by Steamballoon Incorporated
22 * 55 Byward Market Square, 2nd Floor North, Ottawa, ON K1N 9C3, Canada
23 */
24
25 #define _GNU_SOURCE /* for asprintf */
26
27 #include "config.h"
28
29 #ifdef UCLINUX
30
31 #include <stdarg.h>
32 #include <string.h>
33 #include <stdio.h>
34 #include "test.h"
35
36 /* Set from parse_opts.c: */
37 char *child_args; /* Arguments to child when -C is used */
38
39 static char *start_cwd; /* Stores the starting directory for self_exec */
40
asprintf(char ** app,const char * fmt,...)41 int asprintf(char **app, const char *fmt, ...)
42 {
43 va_list ptr;
44 int rv;
45 char *p;
46
47 /*
48 * First iteration - find out size of buffer required and allocate it.
49 */
50 va_start(ptr, fmt);
51 rv = vsnprintf(NULL, 0, fmt, ptr);
52 va_end(ptr);
53
54 p = malloc(++rv); /* allocate the buffer */
55 *app = p;
56 if (!p) {
57 return -1;
58 }
59
60 /*
61 * Second iteration - actually produce output.
62 */
63 va_start(ptr, fmt);
64 rv = vsnprintf(p, rv, fmt, ptr);
65 va_end(ptr);
66
67 return rv;
68 }
69
maybe_run_child(void (* child)(),const char * fmt,...)70 void maybe_run_child(void (*child) (), const char *fmt, ...)
71 {
72 va_list ap;
73 char *child_dir;
74 char *p, *tok;
75 int *iptr, i, j;
76 char *s;
77 char **sptr;
78 char *endptr;
79
80 /* Store the current directory for later use. */
81 start_cwd = getcwd(NULL, 0);
82
83 if (child_args) {
84 char *args = strdup(child_args);
85
86 child_dir = strtok(args, ",");
87 if (strlen(child_dir) == 0) {
88 tst_brkm(TBROK, NULL,
89 "Could not get directory from -C option");
90 return;
91 }
92
93 va_start(ap, fmt);
94
95 for (p = fmt; *p; p++) {
96 tok = strtok(NULL, ",");
97 if (!tok || strlen(tok) == 0) {
98 tst_brkm(TBROK, NULL,
99 "Invalid argument to -C option");
100 return;
101 }
102
103 switch (*p) {
104 case 'd':
105 iptr = va_arg(ap, int *);
106 i = strtol(tok, &endptr, 10);
107 if (*endptr != '\0') {
108 tst_brkm(TBROK, NULL,
109 "Invalid argument to -C option");
110 return;
111 }
112 *iptr = i;
113 break;
114 case 'n':
115 j = va_arg(ap, int);
116 i = strtol(tok, &endptr, 10);
117 if (*endptr != '\0') {
118 tst_brkm(TBROK, NULL,
119 "Invalid argument to -C option");
120 return;
121 }
122 if (j != i) {
123 va_end(ap);
124 free(args);
125 return;
126 }
127 break;
128 case 's':
129 s = va_arg(ap, char *);
130 if (!strncpy(s, tok, strlen(tok) + 1)) {
131 tst_brkm(TBROK, NULL,
132 "Could not strncpy for -C option");
133 return;
134 }
135 break;
136 case 'S':
137 sptr = va_arg(ap, char **);
138 *sptr = strdup(tok);
139 if (!*sptr) {
140 tst_brkm(TBROK, NULL,
141 "Could not strdup for -C option");
142 return;
143 }
144 break;
145 default:
146 tst_brkm(TBROK, NULL,
147 "Format string option %c not implemented",
148 *p);
149 return;
150 }
151 }
152
153 va_end(ap);
154 free(args);
155 if (chdir(child_dir) < 0) {
156 tst_brkm(TBROK, NULL,
157 "Could not change to %s for child", child_dir);
158 return;
159 }
160
161 (*child) ();
162 tst_resm(TWARN, "Child function returned unexpectedly");
163 /* Exit here? or exit silently? */
164 }
165 }
166
self_exec(const char * argv0,const char * fmt,...)167 int self_exec(const char *argv0, const char *fmt, ...)
168 {
169 va_list ap;
170 char *p;
171 char *tmp_cwd;
172 char *arg;
173 int ival;
174 char *str;
175
176 if ((tmp_cwd = getcwd(NULL, 0)) == NULL) {
177 tst_resm(TBROK, "Could not getcwd()");
178 return -1;
179 }
180
181 arg = strdup(tmp_cwd);
182 if (arg == NULL) {
183 tst_resm(TBROK, "Could not produce self_exec string");
184 return -1;
185 }
186
187 va_start(ap, fmt);
188
189 for (p = fmt; *p; p++) {
190 switch (*p) {
191 case 'd':
192 case 'n':
193 ival = va_arg(ap, int);
194 if (asprintf(&arg, "%s,%d", arg, ival) < 0) {
195 tst_resm(TBROK,
196 "Could not produce self_exec string");
197 return -1;
198 }
199 break;
200 case 's':
201 case 'S':
202 str = va_arg(ap, char *);
203 if (asprintf(&arg, "%s,%s", arg, str) < 0) {
204 tst_resm(TBROK,
205 "Could not produce self_exec string");
206 return -1;
207 }
208 break;
209 default:
210 tst_resm(TBROK,
211 "Format string option %c not implemented", *p);
212 return -1;
213 break;
214 }
215 }
216
217 va_end(ap);
218
219 if (chdir(start_cwd) < 0) {
220 tst_resm(TBROK, "Could not change to %s for self_exec",
221 start_cwd);
222 return -1;
223 }
224
225 return execlp(argv0, argv0, "-C", arg, (char *)NULL);
226 }
227
228 #endif /* UCLINUX */
229