1 /* $OpenPackages$ */ 2 /* $OpenBSD: parsevar.c,v 1.2 2004/04/07 13:11:36 espie Exp $ */ 3 /* $NetBSD: parse.c,v 1.29 1997/03/10 21:20:04 christos Exp $ */ 4 5 /* 6 * Copyright (c) 2001 Marc Espie. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OPENBSD 21 * PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #include <ctype.h> 31 #include <stddef.h> 32 #include <stdlib.h> 33 #include <string.h> 34 #include "config.h" 35 #include "defines.h" 36 #include "var.h" 37 #include "varname.h" 38 #include "error.h" 39 #include "cmd_exec.h" 40 #include "parsevar.h" 41 42 static const char *find_op1(const char *); 43 static const char *find_op2(const char *); 44 45 static const char * 46 find_op1(const char *p) 47 { 48 for(;; p++) { 49 if (isspace(*p) || *p == '$' || *p == '\0') 50 break; 51 if (p[strspn(p, "?:!+")] == '=') 52 break; 53 if (p[0] == ':' && p[1] == 's' && p[2] == 'h') 54 break; 55 } 56 return p; 57 } 58 59 static const char * 60 find_op2(const char *p) 61 { 62 for(;; p++) { 63 if (isspace(*p) || *p == '$' || *p == '\0') 64 break; 65 if (p[strspn(p, "?:!+")] == '=') 66 break; 67 } 68 return p; 69 } 70 71 bool 72 Parse_DoVar(const char *line, 73 GSymT *ctxt) /* Context in which to do the assignment */ 74 { 75 const char *arg; 76 char *res1 = NULL, *res2 = NULL; 77 #define VAR_NORMAL 0 78 #define VAR_SUBST 1 79 #define VAR_APPEND 2 80 #define VAR_SHELL 4 81 #define VAR_OPT 8 82 int type; /* Type of assignment */ 83 struct Name name; 84 85 arg = VarName_Get(line, &name, (SymTable *)ctxt, true, 86 FEATURES(FEATURE_SUNSHCMD) ? find_op1 : find_op2); 87 88 while (isspace(*arg)) 89 arg++; 90 91 type = VAR_NORMAL; 92 93 while (*arg != '=' && !isspace(*arg)) { 94 /* Check operator type. */ 95 switch (*arg++) { 96 case '+': 97 if (type & (VAR_OPT|VAR_APPEND)) { 98 VarName_Free(&name); 99 return false; 100 } 101 type |= VAR_APPEND; 102 break; 103 104 case '?': 105 if (type & (VAR_OPT|VAR_APPEND)) { 106 VarName_Free(&name); 107 return false; 108 } 109 type |= VAR_OPT; 110 break; 111 112 case ':': 113 if (FEATURES(FEATURE_SUNSHCMD) && strncmp(arg, "sh", 2) == 0) { 114 type = VAR_SHELL; 115 arg += 2; 116 while (*arg != '=' && *arg != '\0') 117 arg++; 118 } else { 119 if (type & VAR_SUBST) { 120 VarName_Free(&name); 121 return false; 122 } 123 type |= VAR_SUBST; 124 } 125 break; 126 127 case '!': 128 if (type & VAR_SHELL) { 129 VarName_Free(&name); 130 return false; 131 } 132 type |= VAR_SHELL; 133 break; 134 135 default: 136 VarName_Free(&name); 137 return false; 138 } 139 } 140 141 /* Check validity of operator */ 142 if (*arg++ != '=') { 143 VarName_Free(&name); 144 return false; 145 } 146 147 while (isspace(*arg)) 148 arg++; 149 /* If the variable already has a value, we don't do anything. */ 150 if ((type & VAR_OPT) && Var_Valuei(name.s, name.e) != NULL) { 151 VarName_Free(&name); 152 return true; 153 } 154 if (type & VAR_SHELL) { 155 char *err; 156 157 if (strchr(arg, '$') != NULL) { 158 char *sub; 159 /* There's a dollar sign in the command, so perform variable 160 * expansion on the whole thing. */ 161 sub = Var_Subst(arg, NULL, true); 162 res1 = Cmd_Exec(sub, &err); 163 free(sub); 164 } else 165 res1 = Cmd_Exec(arg, &err); 166 167 if (err) 168 Parse_Error(PARSE_WARNING, err, arg); 169 arg = res1; 170 } 171 if (type & VAR_SUBST) { 172 /* 173 * Allow variables in the old value to be undefined, but leave their 174 * invocation alone -- this is done by forcing oldVars to be false. 175 * XXX: This can cause recursive variables, but that's not hard to do, 176 * and this allows someone to do something like 177 * 178 * CFLAGS = $(.INCLUDES) 179 * CFLAGS := -I.. $(CFLAGS) 180 * 181 * And not get an error. 182 */ 183 bool oldOldVars = oldVars; 184 185 oldVars = false; 186 /* ensure the variable is set to something to avoid `variable 187 * is recursive' errors. */ 188 if (Var_Valuei(name.s, name.e) == NULL) 189 Var_Seti(name.s, name.e, "", ctxt); 190 191 res2 = Var_Subst(arg, (SymTable *)ctxt, false); 192 oldVars = oldOldVars; 193 194 arg = res2; 195 } 196 197 if (type & VAR_APPEND) 198 Var_Appendi(name.s, name.e, arg, ctxt); 199 else 200 Var_Seti(name.s, name.e, arg, ctxt); 201 202 VarName_Free(&name); 203 free(res2); 204 free(res1); 205 return true; 206 } 207 208