1 /*
2 * Copyright © 2010 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 */
23
24 #include <assert.h>
25 #include <string.h>
26 #include <ctype.h>
27 #include "glcpp.h"
28 #include "main/core.h" /* for isblank() on MSVC */
29
30 void
glcpp_error(YYLTYPE * locp,glcpp_parser_t * parser,const char * fmt,...)31 glcpp_error (YYLTYPE *locp, glcpp_parser_t *parser, const char *fmt, ...)
32 {
33 va_list ap;
34
35 parser->error = 1;
36 parser->info_log = hieralloc_asprintf_append(parser->info_log,
37 "%u:%u(%u): "
38 "preprocessor error: ",
39 locp->source,
40 locp->first_line,
41 locp->first_column);
42 va_start(ap, fmt);
43 parser->info_log = hieralloc_vasprintf_append(parser->info_log, fmt, ap);
44 va_end(ap);
45 parser->info_log = hieralloc_strdup_append(parser->info_log, "\n");
46 }
47
48 void
glcpp_warning(YYLTYPE * locp,glcpp_parser_t * parser,const char * fmt,...)49 glcpp_warning (YYLTYPE *locp, glcpp_parser_t *parser, const char *fmt, ...)
50 {
51 va_list ap;
52
53 parser->info_log = hieralloc_asprintf_append(parser->info_log,
54 "%u:%u(%u): "
55 "preprocessor warning: ",
56 locp->source,
57 locp->first_line,
58 locp->first_column);
59 va_start(ap, fmt);
60 parser->info_log = hieralloc_vasprintf_append(parser->info_log, fmt, ap);
61 va_end(ap);
62 parser->info_log = hieralloc_strdup_append(parser->info_log, "\n");
63 }
64
65 /* Searches backwards for '^ *#' from a given starting point. */
66 static int
in_directive(const char * shader,const char * ptr)67 in_directive(const char *shader, const char *ptr)
68 {
69 assert(ptr >= shader);
70
71 /* Search backwards for '#'. If we find a \n first, it doesn't count */
72 for (; ptr >= shader && *ptr != '#'; ptr--) {
73 if (*ptr == '\n')
74 return 0;
75 }
76 if (ptr >= shader) {
77 /* Found '#'...look for spaces preceded by a newline */
78 for (ptr--; ptr >= shader && isblank(*ptr); ptr--);
79 // FIXME: I don't think the '\n' case can happen
80 if (ptr < shader || *ptr == '\n')
81 return 1;
82 }
83 return 0;
84 }
85
86 /* Remove any line continuation characters in preprocessing directives.
87 * However, ignore any in GLSL code, as "There is no line continuation
88 * character" (1.30 page 9) in GLSL.
89 */
90 static char *
remove_line_continuations(glcpp_parser_t * ctx,const char * shader)91 remove_line_continuations(glcpp_parser_t *ctx, const char *shader)
92 {
93 int in_continued_line = 0;
94 int extra_newlines = 0;
95 char *clean = hieralloc_strdup(ctx, "");
96 const char *search_start = shader;
97 const char *newline;
98 while ((newline = strchr(search_start, '\n')) != NULL) {
99 const char *backslash = NULL;
100
101 /* # of characters preceding the newline. */
102 int n = newline - shader;
103
104 /* Find the preceding '\', if it exists */
105 if (n >= 1 && newline[-1] == '\\')
106 backslash = newline - 1;
107 else if (n >= 2 && newline[-1] == '\r' && newline[-2] == '\\')
108 backslash = newline - 2;
109
110 /* Double backslashes don't count (the backslash is escaped) */
111 if (backslash != NULL && backslash[-1] == '\\') {
112 backslash = NULL;
113 }
114
115 if (backslash != NULL) {
116 /* We found a line continuation, but do we care? */
117 if (!in_continued_line) {
118 if (in_directive(shader, backslash)) {
119 in_continued_line = 1;
120 extra_newlines = 0;
121 }
122 }
123 if (in_continued_line) {
124 /* Copy everything before the \ */
125 clean = hieralloc_strndup_append(clean, shader, backslash - shader);
126 shader = newline + 1;
127 extra_newlines++;
128 }
129 } else if (in_continued_line) {
130 /* Copy everything up to and including the \n */
131 clean = hieralloc_strndup_append(clean, shader, newline - shader + 1);
132 shader = newline + 1;
133 /* Output extra newlines to make line numbers match */
134 for (; extra_newlines > 0; extra_newlines--)
135 clean = hieralloc_strdup_append(clean, "\n");
136 in_continued_line = 0;
137 }
138 search_start = newline + 1;
139 }
140 clean = hieralloc_strdup_append(clean, shader);
141 return clean;
142 }
143
144 int
preprocess(void * hieralloc_ctx,const char ** shader,char ** info_log,const struct gl_extensions * extensions,int api)145 preprocess(void *hieralloc_ctx, const char **shader, char **info_log,
146 const struct gl_extensions *extensions, int api)
147 {
148 int errors;
149 glcpp_parser_t *parser = glcpp_parser_create (extensions, api);
150 *shader = remove_line_continuations(parser, *shader);
151
152 glcpp_lex_set_source_string (parser, *shader);
153
154 glcpp_parser_parse (parser);
155
156 if (parser->skip_stack)
157 glcpp_error (&parser->skip_stack->loc, parser, "Unterminated #if\n");
158
159 *info_log = hieralloc_strdup_append(*info_log, parser->info_log);
160
161 hieralloc_steal(hieralloc_ctx, parser->output);
162 *shader = parser->output;
163
164 errors = parser->error;
165 glcpp_parser_destroy (parser);
166 return errors;
167 }
168