| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: qdparse.c,v 1.2 2004/04/08 01:36:15 mdw Exp $ |
| 4 | * |
| 5 | * Quick-and-dirty parser |
| 6 | * |
| 7 | * (c) 2004 Straylight/Edgeware |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Catacomb. |
| 13 | * |
| 14 | * Catacomb is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU Library General Public License as |
| 16 | * published by the Free Software Foundation; either version 2 of the |
| 17 | * License, or (at your option) any later version. |
| 18 | * |
| 19 | * Catacomb is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU Library General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU Library General Public |
| 25 | * License along with Catacomb; if not, write to the Free |
| 26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 27 | * MA 02111-1307, USA. |
| 28 | */ |
| 29 | |
| 30 | /*----- Header files ------------------------------------------------------*/ |
| 31 | |
| 32 | #include <ctype.h> |
| 33 | #include <string.h> |
| 34 | |
| 35 | #include "qdparse.h" |
| 36 | |
| 37 | /*----- Main code ---------------------------------------------------------*/ |
| 38 | |
| 39 | /* --- @qd_skipspc@ --- * |
| 40 | * |
| 41 | * Arguments: @qd_parse *qd@ = context |
| 42 | * |
| 43 | * Returns: --- |
| 44 | * |
| 45 | * Use: Skips spaces in the string. No errors. |
| 46 | */ |
| 47 | |
| 48 | void qd_skipspc(qd_parse *qd) |
| 49 | { |
| 50 | while (isspace((unsigned char)*qd->p)) |
| 51 | qd->p++; |
| 52 | } |
| 53 | |
| 54 | /* --- @qd_delim@ --- * |
| 55 | * |
| 56 | * Arguments: @qd_parse *qd@ = context |
| 57 | * @int ch@ = character to compare with |
| 58 | * |
| 59 | * Returns: Nonzero if it was, zero if it wasn't. |
| 60 | * |
| 61 | * Use: Checks the next (non-whitespace) character is what we |
| 62 | * expect. If it is, the character is eaten; otherwise it's no |
| 63 | * big deal. |
| 64 | */ |
| 65 | |
| 66 | int qd_delim(qd_parse *qd, int ch) |
| 67 | { |
| 68 | qd_skipspc(qd); |
| 69 | if (*qd->p != ch) |
| 70 | return (0); |
| 71 | qd->p++; |
| 72 | return (1); |
| 73 | } |
| 74 | |
| 75 | /* --- @qd_enum@ --- * |
| 76 | * |
| 77 | * Arguments: @qd_parse *qd@ = context |
| 78 | * @const char *e@ = list of enum strings, space separated |
| 79 | * |
| 80 | * Returns: Index of the string matched, or @-1@. |
| 81 | * |
| 82 | * Use: Matches a keyword. |
| 83 | */ |
| 84 | |
| 85 | int qd_enum(qd_parse *qd, const char *e) |
| 86 | { |
| 87 | size_t n; |
| 88 | int i = 0; |
| 89 | |
| 90 | qd_skipspc(qd); |
| 91 | for (;;) { |
| 92 | e += strspn(e, ", "); |
| 93 | if (!*e) break; |
| 94 | n = strcspn(e, ", "); |
| 95 | if (strncmp(qd->p, e, n) == 0 && !isalnum((unsigned char)qd->p[n])) { |
| 96 | qd->p += n; |
| 97 | return (i); |
| 98 | } |
| 99 | i++; e += n; |
| 100 | } |
| 101 | qd->e = "unrecognized keyword"; |
| 102 | return (-1); |
| 103 | } |
| 104 | |
| 105 | /* --- @qd_getmp@ --- * |
| 106 | * |
| 107 | * Arguments: @qd_parse *qd@ = context |
| 108 | * |
| 109 | * Returns: The integer extracted, or null. |
| 110 | * |
| 111 | * Use: Parses a multiprecision integer from a string. |
| 112 | */ |
| 113 | |
| 114 | mp *qd_getmp(qd_parse *qd) |
| 115 | { |
| 116 | char *q; |
| 117 | mp *m; |
| 118 | |
| 119 | qd_skipspc(qd); |
| 120 | m = mp_readstring(MP_NEW, qd->p, &q, 0); |
| 121 | if (m && !isalnum((unsigned char)*q)) |
| 122 | qd->p = q; |
| 123 | else { |
| 124 | mp_drop(m); |
| 125 | qd->e = "bad number"; |
| 126 | } |
| 127 | return (m); |
| 128 | } |
| 129 | |
| 130 | /* --- @qd_eofp@ --- * |
| 131 | * |
| 132 | * Arguments: @qd_parse *qd@ = context |
| 133 | * |
| 134 | * Returns: Nonzero if at EOF, zero otherwise. |
| 135 | */ |
| 136 | |
| 137 | int qd_eofp(qd_parse *qd) |
| 138 | { |
| 139 | qd_skipspc(qd); |
| 140 | return (!*qd->p); |
| 141 | } |
| 142 | |
| 143 | /*----- That's all, folks -------------------------------------------------*/ |