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