src/glsl/s_expression.cpp

   1 /* -*- c++ -*- */
   2 /*
   3  * Copyright © 2010 Intel Corporation
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22  * DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 #include <cstdio>
  26 #include <cstdlib>
  27 #include <cstring>
  28 #include <assert.h>
  29 #include "s_expression.h"
  30
  31 s_symbol::s_symbol(const char *tmp)
  32 {
  33    this->str = talloc_strdup (this, tmp);
  34    assert(this->str != NULL);
  35 }
  36
  37 s_list::s_list()
  38 {
  39 }
  40
  41 unsigned
  42 s_list::length() const
  43 {
  44    unsigned i = 0;
  45    foreach_iter(exec_list_iterator, it, this->subexpressions) {
  46       i++;
  47    }
  48    return i;
  49 }
  50
  51 static s_expression *
  52 read_atom(void *ctx, const char *& src)
  53 {
  54    char buf[101];
  55    int n;
  56    if (sscanf(src, " %100[^( \v\t\r\n)]%n", buf, &n) != 1)
  57       return NULL; // no atom
  58    src += n;
  59
  60    // Check if the atom is a number.
  61    char *float_end = NULL;
  62    double f = strtod(buf, &float_end);
  63    if (float_end != buf) {
  64       char *int_end = NULL;
  65       int i = strtol(buf, &int_end, 10);
  66       // If strtod matched more characters, it must have a decimal part
  67       if (float_end > int_end)
  68          return new(ctx) s_float(f);
  69
  70       return new(ctx) s_int(i);
  71    }
  72    // Not a number; return a symbol.
  73    return new(ctx) s_symbol(buf);
  74 }
  75
  76 s_expression *
  77 s_expression::read_expression(void *ctx, const char *&src)
  78 {
  79    assert(src != NULL);
  80
  81    s_expression *atom = read_atom(ctx, src);
  82    if (atom != NULL)
  83       return atom;
  84
  85    char c;
  86    int n;
  87    if (sscanf(src, " %c%n", &c, &n) == 1 && c == '(') {
  88       src += n;
  89
  90       s_list *list = new(ctx) s_list;
  91       s_expression *expr;
  92
  93       while ((expr = read_expression(ctx, src)) != NULL) {
  94          list->subexpressions.push_tail(expr);
  95       }
  96       if (sscanf(src, " %c%n", &c, &n) != 1 || c != ')') {
  97          printf("Unclosed expression (check your parenthesis).\n");
  98          return NULL;
  99       }
 100       src += n;
 101       return list;
 102    }
 103    return NULL;
 104 }
 105
 106 void s_int::print()
 107 {
 108    printf("%d", this->val);
 109 }
 110
 111 void s_float::print()
 112 {
 113    printf("%f", this->val);
 114 }
 115
 116 void s_symbol::print()
 117 {
 118    printf("%s", this->str);
 119 }
 120
 121 void s_list::print()
 122 {
 123    printf("(");
 124    foreach_iter(exec_list_iterator, it, this->subexpressions) {
 125       s_expression *expr = (s_expression*) it.get();
 126       expr->print();
 127       printf(" ");
 128    }
 129    printf(")");
 130 }
 131