1 #pragma ident "%Z%%M% %I% %E% SMI" 2 3 /* 4 * Copyright 1987, 1988 by MIT Student Information Processing Board 5 * 6 * For copyright info, see copyright.h. 7 */ 8 9 #include "ss_internal.h" 10 #include "copyright.h" 11 12 /* global indicating if we should be printing debug messages */ 13 extern int g_displayDebugSS; 14 15 16 enum parse_mode { WHITESPACE, TOKEN, QUOTED_STRING }; 17 18 /* 19 * parse(line_ptr, argc_ptr) 20 * 21 * Function: 22 * Parses line, dividing at whitespace, into tokens, returns 23 * the "argc" and "argv" values. 24 * Arguments: 25 * line_ptr (char *) 26 * Pointer to text string to be parsed. 27 * argc_ptr (int *) 28 * Where to put the "argc" (number of tokens) value. 29 * Returns: 30 * argv (char **) 31 * Series of pointers to parsed tokens. 32 */ 33 34 #define NEW_ARGV(old,n) (char **)realloc((char *)old,\ 35 (unsigned)(n+2)*sizeof(char*)) 36 37 char **ss_parse (sci_idx, line_ptr, argc_ptr) 38 int sci_idx; 39 register char *line_ptr; 40 int *argc_ptr; 41 { 42 register char **argv, *cp; 43 register int argc; 44 register enum parse_mode parse_mode; 45 46 argv = (char **) malloc (sizeof(char *)); 47 if (argv == (char **)NULL) { 48 ss_error(sci_idx, errno, "Can't allocate storage"); 49 *argc_ptr = 0; 50 return(argv); 51 } 52 *argv = (char *)NULL; 53 54 argc = 0; 55 56 parse_mode = WHITESPACE; /* flushing whitespace */ 57 cp = line_ptr; /* cp is for output */ 58 while (1) { 59 #ifdef DEBUG 60 { 61 if (g_displayDebugSS) 62 printf ("character `%c', mode %d\n", 63 *line_ptr, parse_mode); 64 } 65 #endif 66 while (parse_mode == WHITESPACE) { 67 if (*line_ptr == '\0') 68 goto end_of_line; 69 if (*line_ptr == ' ' || *line_ptr == '\t') { 70 line_ptr++; 71 continue; 72 } 73 if (*line_ptr == '"') { 74 /* go to quoted-string mode */ 75 parse_mode = QUOTED_STRING; 76 cp = line_ptr++; 77 argv = NEW_ARGV (argv, argc); 78 argv[argc++] = cp; 79 argv[argc] = NULL; 80 } 81 else { 82 /* random-token mode */ 83 parse_mode = TOKEN; 84 cp = line_ptr; 85 argv = NEW_ARGV (argv, argc); 86 argv[argc++] = line_ptr; 87 argv[argc] = NULL; 88 } 89 } 90 while (parse_mode == TOKEN) { 91 if (*line_ptr == '\0') { 92 *cp++ = '\0'; 93 goto end_of_line; 94 } 95 else if (*line_ptr == ' ' || *line_ptr == '\t') { 96 *cp++ = '\0'; 97 line_ptr++; 98 parse_mode = WHITESPACE; 99 } 100 else if (*line_ptr == '"') { 101 line_ptr++; 102 parse_mode = QUOTED_STRING; 103 } 104 else { 105 *cp++ = *line_ptr++; 106 } 107 } 108 while (parse_mode == QUOTED_STRING) { 109 if (*line_ptr == '\0') { 110 ss_error (sci_idx, 0, 111 "Unbalanced quotes in command line"); 112 free (argv); 113 *argc_ptr = 0; 114 return NULL; 115 } 116 else if (*line_ptr == '"') { 117 if (*++line_ptr == '"') { 118 *cp++ = '"'; 119 line_ptr++; 120 } 121 else { 122 parse_mode = TOKEN; 123 } 124 } 125 else { 126 *cp++ = *line_ptr++; 127 } 128 } 129 } 130 end_of_line: 131 *argc_ptr = argc; 132 #ifdef DEBUG 133 134 if (g_displayDebugSS) 135 { 136 int i; 137 printf ("argc = %d\n", argc); 138 for (i = 0; i <= argc; i++) 139 printf ("\targv[%2d] = `%s'\n", i, 140 argv[i] ? argv[i] : "<NULL>"); 141 } 142 #endif 143 return(argv); 144 } 145