1 /* 2 * Copyright (c) 2000, 2001, 2002, 2003, 2004 by Martin C. Shepherd. 3 * 4 * All rights reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, and/or sell copies of the Software, and to permit persons 11 * to whom the Software is furnished to do so, provided that the above 12 * copyright notice(s) and this permission notice appear in all copies of 13 * the Software and that both the above copyright notice(s) and this 14 * permission notice appear in supporting documentation. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT 19 * OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 20 * HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL 21 * INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING 22 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, 23 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 24 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 25 * 26 * Except as contained in this notice, the name of a copyright holder 27 * shall not be used in advertising or otherwise to promote the sale, use 28 * or other dealings in this Software without prior written authorization 29 * of the copyright holder. 30 */ 31 32 #pragma ident "%Z%%M% %I% %E% SMI" 33 34 #include <stdlib.h> 35 #include <string.h> 36 #include <errno.h> 37 #include <stdarg.h> 38 39 #include "errmsg.h" 40 41 /* 42 * Encapsulate the error reporting buffer in an opaque object. 43 */ 44 struct ErrMsg { 45 char msg[ERR_MSG_LEN+1]; /* An error message */ 46 }; 47 48 /*....................................................................... 49 * Create a new error-message object. 50 * 51 * Output: 52 * return ErrMsg * The new object, or NULL on error. 53 */ 54 ErrMsg *_new_ErrMsg(void) 55 { 56 ErrMsg *err; /* The object to be returned */ 57 /* 58 * Allocate the container. 59 */ 60 err = malloc(sizeof(ErrMsg)); 61 if(!err) { 62 errno = ENOMEM; 63 return NULL; 64 }; 65 /* 66 * Before attempting any operation that might fail, initialize the 67 * container at least up to the point at which it can safely be passed 68 * to del_ErrMsg(). 69 */ 70 err->msg[0] = '\0'; 71 return err; 72 } 73 74 /*....................................................................... 75 * Delete an error-message object. 76 * 77 * Input: 78 * err ErrMsg * The object to be deleted. 79 * Output: 80 * return ErrMsg * The deleted object (always NULL). 81 */ 82 ErrMsg *_del_ErrMsg(ErrMsg *err) 83 { 84 if(err) { 85 free(err); 86 }; 87 return NULL; 88 } 89 90 /*....................................................................... 91 * Record the concatenation of a list of string arguments in an error 92 * message object. The last argument must be END_ERR_MSG to terminate 93 * the argument list. 94 * 95 * Input: 96 * err ErrMsg * The error-message container. 97 * ... const char * Zero or more strings to be concatenated in buff[]. 98 * ... const char * The last argument must always be END_ERR_MSG to 99 * terminate the argument list. 100 */ 101 void _err_record_msg(ErrMsg *err, ...) 102 { 103 va_list ap; /* The variable argument list */ 104 const char *s; /* The string being printed */ 105 size_t msglen = 0; /* The total length of the message */ 106 /* 107 * Nowhere to record the result? 108 */ 109 if(!err) { 110 errno = EINVAL; 111 return; 112 }; 113 /* 114 * Concatenate the list of argument strings in err->msg[]. 115 */ 116 va_start(ap, err); 117 while((s = va_arg(ap, const char *)) != END_ERR_MSG) { 118 /* 119 * How much room is left in the output buffer (note that the output 120 * buffer has ERR_MSG_LEN+1 elements). 121 */ 122 int nleft = ERR_MSG_LEN - msglen; 123 /* 124 * How long is the next string to be appended? 125 */ 126 size_t slen = strlen(s); 127 /* 128 * If there is any room left, append as much of the string 129 * as will fit. 130 */ 131 if(nleft > 0) { 132 int nnew = slen < nleft ? slen : nleft; 133 strncpy(err->msg + msglen, s, nnew); 134 msglen += nnew; 135 }; 136 }; 137 va_end(ap); 138 /* 139 * Terminate the message. 140 */ 141 err->msg[msglen] = '\0'; 142 return; 143 } 144 145 /*....................................................................... 146 * Return a pointer to the error message buffer. 147 * 148 * Input: 149 * err ErrMsg * The container of the error message buffer. 150 * Output: 151 * return char * The current error message, or NULL if err==NULL. 152 */ 153 char *_err_get_msg(ErrMsg *err) 154 { 155 return err ? err->msg : NULL; 156 } 157 158 /*....................................................................... 159 * Replace the current error message with an empty string. 160 * 161 * Input: 162 * err ErrMsg * The container of the error message buffer. 163 */ 164 void _err_clear_msg(ErrMsg *err) 165 { 166 if(err) 167 err->msg[0] = '\0'; 168 } 169 170