1/* $NetBSD: defined.c,v 1.2 2019/11/16 12:26:54 tkusumi Exp $ */ 2 3/*- 4 * Copyright (c) 2017 The NetBSD Foundation, Inc. 5 * Copyright (c) 2016 The DragonFly Project 6 * Copyright (c) 2014 The FreeBSD Foundation 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to The NetBSD Foundation 10 * by Tomohiro Kusumi <kusumi.tomohiro@gmail.com>. 11 * 12 * This software was developed by Edward Tomasz Napierala under sponsorship 13 * from the FreeBSD Foundation. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 */ 37#include <sys/cdefs.h> 38__RCSID("$NetBSD: defined.c,v 1.2 2019/11/16 12:26:54 tkusumi Exp $"); 39 40/* 41 * All the "defined" stuff is for handling variables, 42 * such as ${OSNAME}, in maps. 43 */ 44 45#include <sys/types.h> 46#include <sys/utsname.h> 47#include <assert.h> 48#include <ctype.h> 49#include <stdio.h> 50#include <stdlib.h> 51#include <string.h> 52#include <unistd.h> 53 54#include "common.h" 55 56static TAILQ_HEAD(, defined_value) defined_values; 57 58static const char * 59defined_find(const char *name) 60{ 61 struct defined_value *d; 62 63 TAILQ_FOREACH(d, &defined_values, d_next) { 64 if (strcmp(d->d_name, name) == 0) 65 return d->d_value; 66 } 67 68 return NULL; 69} 70 71char * 72defined_expand(const char *string) 73{ 74 const char *value; 75 char c, *expanded, *name; 76 int ret; 77 size_t i, before_len = 0, name_off = 0, name_len = 0, after_off = 0; 78 bool backslashed = false, bracketed = false; 79 80 expanded = checked_strdup(string); 81 82 for (i = 0; string[i] != '\0'; i++) { 83 c = string[i]; 84 if (c == '\\' && backslashed == false) { 85 backslashed = true; 86 continue; 87 } 88 if (backslashed) { 89 backslashed = false; 90 continue; 91 } 92 backslashed = false; 93 if (c != '$') 94 continue; 95 96 /* 97 * The 'before_len' variable contains the number 98 * of characters before the '$'. 99 */ 100 before_len = i; 101 assert(i + 1 < strlen(string)); 102 if (string[i + 1] == '{') 103 bracketed = true; 104 105 if (string[i + 1] == '\0') { 106 log_warnx("truncated variable"); 107 return NULL; 108 } 109 110 /* 111 * Skip '$'. 112 */ 113 i++; 114 115 if (bracketed) { 116 if (string[i + 1] == '\0') { 117 log_warnx("truncated variable"); 118 return NULL; 119 } 120 121 /* 122 * Skip '{'. 123 */ 124 i++; 125 } 126 127 /* 128 * The 'name_off' variable contains the number 129 * of characters before the variable name, 130 * including the "$" or "${". 131 */ 132 name_off = i; 133 134 for (; string[i] != '\0'; i++) { 135 c = string[i]; 136 /* 137 * XXX: Decide on the set of characters that can be 138 * used in a variable name. 139 */ 140 if (isalnum((unsigned char)c) || c == '_') 141 continue; 142 143 /* 144 * End of variable name. 145 */ 146 if (bracketed) { 147 if (c != '}') 148 continue; 149 150 /* 151 * The 'after_off' variable contains the number 152 * of characters before the rest of the string, 153 * i.e. after the variable name. 154 */ 155 after_off = i + 1; 156 assert(i > 1); 157 assert(i - 1 > name_off); 158 name_len = i - name_off; 159 break; 160 } 161 162 after_off = i; 163 assert(i > 1); 164 assert(i > name_off); 165 name_len = i - name_off; 166 break; 167 } 168 169 name = strndup(string + name_off, name_len); 170 if (name == NULL) 171 log_err(1, "strndup"); 172 value = defined_find(name); 173 if (value == NULL) { 174 log_warnx("undefined variable ${%s}", name); 175 return NULL; 176 } 177 178 /* 179 * Concatenate it back. 180 */ 181 ret = asprintf(&expanded, "%.*s%s%s", 182 (int)before_len, string, value, string + after_off); 183 if (ret < 0) 184 log_err(1, "asprintf"); 185 186 //log_debugx("\"%s\" expanded to \"%s\"", string, expanded); 187 free(name); 188 189 /* 190 * Figure out where to start searching for next variable. 191 */ 192 string = expanded; 193 i = before_len + strlen(value); 194 backslashed = bracketed = false; 195 before_len = name_off = name_len = after_off = 0; 196 assert(i <= strlen(string)); 197 } 198 199 if (before_len != 0 || name_off != 0 || name_len != 0 200 || after_off != 0) { 201 log_warnx("truncated variable"); 202 return NULL; 203 } 204 205 return expanded; 206} 207 208static void 209defined_add(const char *name, const char *value) 210{ 211 struct defined_value *d; 212 const char *found; 213 214 found = defined_find(name); 215 if (found != NULL) 216 log_errx(1, "variable %s already defined", name); 217 218 log_debugx("defining variable %s=%s", name, value); 219 220 d = calloc(1, sizeof(*d)); 221 if (d == NULL) 222 log_err(1, "calloc"); 223 d->d_name = checked_strdup(name); 224 d->d_value = checked_strdup(value); 225 226 TAILQ_INSERT_TAIL(&defined_values, d, d_next); 227} 228 229void 230defined_parse_and_add(char *def) 231{ 232 char *name, *value; 233 234 value = def; 235 name = strsep(&value, "="); 236 237 if (value == NULL || value[0] == '\0') 238 log_errx(1, "missing variable value"); 239 if (name == NULL || name[0] == '\0') 240 log_errx(1, "missing variable name"); 241 242 defined_add(name, value); 243} 244 245void 246defined_init(void) 247{ 248 struct utsname name; 249 int error; 250 251 TAILQ_INIT(&defined_values); 252 253 error = uname(&name); 254 if (error != 0) 255 log_err(1, "uname"); 256 257 defined_add("ARCH", name.machine); 258 defined_add("CPU", name.machine); 259 defined_add("DOLLAR", "$"); 260 defined_add("HOST", name.nodename); 261 defined_add("OSNAME", name.sysname); 262 defined_add("OSREL", name.release); 263 defined_add("OSVERS", name.version); 264} 265