1 /* Implementation of the GETENV g77, and 2 GET_ENVIRONMENT_VARIABLE F2003, intrinsics. 3 Copyright (C) 2004-2019 Free Software Foundation, Inc. 4 Contributed by Janne Blomqvist. 5 6 This file is part of the GNU Fortran 95 runtime library (libgfortran). 7 8 Libgfortran is free software; you can redistribute it and/or 9 modify it under the terms of the GNU General Public 10 License as published by the Free Software Foundation; either 11 version 3 of the License, or (at your option) any later version. 12 13 Libgfortran is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 Under Section 7 of GPL version 3, you are granted additional 19 permissions described in the GCC Runtime Library Exception, version 20 3.1, as published by the Free Software Foundation. 21 22 You should have received a copy of the GNU General Public License and 23 a copy of the GCC Runtime Library Exception along with this program; 24 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 25 <http://www.gnu.org/licenses/>. */ 26 27 #include "libgfortran.h" 28 #include <string.h> 29 30 31 /* GETENV (NAME, VALUE), g77 intrinsic for retrieving the value of 32 an environment variable. The name of the variable is specified in 33 NAME, and the result is stored into VALUE. */ 34 35 void PREFIX(getenv) (char *, char *, gfc_charlen_type, gfc_charlen_type); 36 export_proto_np(PREFIX(getenv)); 37 38 void 39 PREFIX(getenv) (char * name, char * value, gfc_charlen_type name_len, 40 gfc_charlen_type value_len) 41 { 42 char *name_nt; 43 char *res = NULL; 44 45 if (name == NULL || value == NULL) 46 runtime_error ("Both arguments to getenv are mandatory."); 47 48 if (value_len < 1 || name_len < 1) 49 runtime_error ("Zero length string(s) passed to getenv."); 50 else 51 memset (value, ' ', value_len); /* Blank the string. */ 52 53 /* Make a null terminated copy of the string. */ 54 name_nt = fc_strdup (name, name_len); 55 56 res = getenv(name_nt); 57 58 free (name_nt); 59 60 /* If res is NULL, it means that the environment variable didn't 61 exist, so just return. */ 62 if (res == NULL) 63 return; 64 65 cf_strcpy (value, value_len, res); 66 } 67 68 69 /* GET_ENVIRONMENT_VARIABLE (name, [value, length, status, trim_name]) 70 is a F2003 intrinsic for getting an environment variable. */ 71 72 /* Status codes specifyed by the standard. */ 73 #define GFC_SUCCESS 0 74 #define GFC_VALUE_TOO_SHORT -1 75 #define GFC_NAME_DOES_NOT_EXIST 1 76 77 /* This is also specified by the standard and means that the 78 processor doesn't support environment variables. At the moment, 79 gfortran doesn't use it. */ 80 #define GFC_NOT_SUPPORTED 2 81 82 /* Processor-specific failure code. */ 83 #define GFC_FAILURE 42 84 85 extern void get_environment_variable_i4 (char *, char *, GFC_INTEGER_4 *, 86 GFC_INTEGER_4 *, GFC_LOGICAL_4 *, 87 gfc_charlen_type, gfc_charlen_type); 88 iexport_proto(get_environment_variable_i4); 89 90 void 91 get_environment_variable_i4 (char *name, char *value, GFC_INTEGER_4 *length, 92 GFC_INTEGER_4 *status, GFC_LOGICAL_4 *trim_name, 93 gfc_charlen_type name_len, 94 gfc_charlen_type value_len) 95 { 96 int stat = GFC_SUCCESS; 97 gfc_charlen_type res_len = 0; 98 char *name_nt; 99 char *res; 100 101 if (name == NULL) 102 runtime_error ("Name is required for get_environment_variable."); 103 104 if (value == NULL && length == NULL && status == NULL && trim_name == NULL) 105 return; 106 107 if (name_len < 1) 108 runtime_error ("Zero-length string passed as name to " 109 "get_environment_variable."); 110 111 if (value != NULL) 112 { 113 if (value_len < 1) 114 runtime_error ("Zero-length string passed as value to " 115 "get_environment_variable."); 116 else 117 memset (value, ' ', value_len); /* Blank the string. */ 118 } 119 120 if ((!trim_name) || *trim_name) 121 name_nt = fc_strdup (name, name_len); 122 else 123 name_nt = fc_strdup_notrim (name, name_len); 124 125 res = getenv(name_nt); 126 127 free (name_nt); 128 129 if (res == NULL) 130 stat = GFC_NAME_DOES_NOT_EXIST; 131 else 132 { 133 res_len = strlen(res); 134 if (value != NULL) 135 { 136 if (value_len < res_len) 137 { 138 memcpy (value, res, value_len); 139 stat = GFC_VALUE_TOO_SHORT; 140 } 141 else 142 memcpy (value, res, res_len); 143 } 144 } 145 146 if (status != NULL) 147 *status = stat; 148 149 if (length != NULL) 150 *length = res_len; 151 } 152 iexport(get_environment_variable_i4); 153 154 155 /* INTEGER*8 wrapper for get_environment_variable. */ 156 157 extern void get_environment_variable_i8 (char *, char *, GFC_INTEGER_8 *, 158 GFC_INTEGER_8 *, GFC_LOGICAL_8 *, 159 gfc_charlen_type, gfc_charlen_type); 160 export_proto(get_environment_variable_i8); 161 162 void 163 get_environment_variable_i8 (char *name, char *value, GFC_INTEGER_8 *length, 164 GFC_INTEGER_8 *status, GFC_LOGICAL_8 *trim_name, 165 gfc_charlen_type name_len, 166 gfc_charlen_type value_len) 167 { 168 GFC_INTEGER_4 length4, status4; 169 GFC_LOGICAL_4 trim_name4; 170 171 if (trim_name) 172 trim_name4 = *trim_name; 173 174 get_environment_variable_i4 (name, value, &length4, &status4, 175 trim_name ? &trim_name4 : NULL, 176 name_len, value_len); 177 178 if (length) 179 *length = length4; 180 181 if (status) 182 *status = status4; 183 } 184