1 /* scan-decls.c - Extracts declarations from cpp output.
2 Copyright (C) 1993, 1995, 1997, 1998,
3 1999, 2000, 2003, 2004 Free Software Foundation, Inc.
4
5 This program is free software; you can redistribute it and/or modify it
6 under the terms of the GNU General Public License as published by the
7 Free Software Foundation; either version 2, or (at your option) any
8 later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18
19 Written by Per Bothner <bothner@cygnus.com>, July 1993. */
20
21 #include "bconfig.h"
22 #include "system.h"
23 #include "coretypes.h"
24 #include "tm.h"
25 #include "cpplib.h"
26 #include "scan.h"
27
28 static void skip_to_closing_brace (cpp_reader *);
29 static const cpp_token *get_a_token (cpp_reader *);
30
31 int brace_nesting = 0;
32
33 /* The first extern_C_braces_length elements of extern_C_braces
34 indicate the (brace nesting levels of) left braces that were
35 prefixed by extern "C". */
36 int extern_C_braces_length = 0;
37 /* 20 is not enough anymore on Solaris 9. */
38 #define MAX_EXTERN_C_BRACES 200
39 char extern_C_braces[MAX_EXTERN_C_BRACES];
40 #define in_extern_C_brace (extern_C_braces_length>0)
41
42 /* True if the function declaration currently being scanned is
43 prefixed by extern "C". */
44 int current_extern_C = 0;
45
46 /* Get a token but skip padding. */
47 static const cpp_token *
get_a_token(cpp_reader * pfile)48 get_a_token (cpp_reader *pfile)
49 {
50 for (;;)
51 {
52 const cpp_token *result = cpp_get_token (pfile);
53 if (result->type != CPP_PADDING)
54 return result;
55 }
56 }
57
58 static void
skip_to_closing_brace(cpp_reader * pfile)59 skip_to_closing_brace (cpp_reader *pfile)
60 {
61 int nesting = 1;
62 for (;;)
63 {
64 enum cpp_ttype token = get_a_token (pfile)->type;
65
66 if (token == CPP_EOF)
67 break;
68 if (token == CPP_OPEN_BRACE)
69 nesting++;
70 if (token == CPP_CLOSE_BRACE && --nesting == 0)
71 break;
72 }
73 }
74
75 /* This function scans a C source file (actually, the output of cpp),
76 reading from FP. It looks for function declarations, and
77 external variable declarations.
78
79 The following grammar (as well as some extra stuff) is recognized:
80
81 declaration:
82 (decl-specifier)* declarator ("," declarator)* ";"
83 decl-specifier:
84 identifier
85 keyword
86 extern "C"
87 declarator:
88 (ptr-operator)* dname [ "(" argument-declaration-list ")" ]
89 ptr-operator:
90 ("*" | "&") ("const" | "volatile")*
91 dname:
92 identifier
93
94 Here dname is the actual name being declared.
95 */
96
97 int
scan_decls(cpp_reader * pfile,int argc ATTRIBUTE_UNUSED,char ** argv ATTRIBUTE_UNUSED)98 scan_decls (cpp_reader *pfile, int argc ATTRIBUTE_UNUSED,
99 char **argv ATTRIBUTE_UNUSED)
100 {
101 int saw_extern, saw_inline;
102 cpp_token prev_id;
103 const cpp_token *token;
104
105 new_statement:
106 token = get_a_token (pfile);
107
108 handle_statement:
109 current_extern_C = 0;
110 saw_extern = 0;
111 saw_inline = 0;
112 if (token->type == CPP_OPEN_BRACE)
113 {
114 /* Pop an 'extern "C"' nesting level, if appropriate. */
115 if (extern_C_braces_length
116 && extern_C_braces[extern_C_braces_length - 1] == brace_nesting)
117 extern_C_braces_length--;
118 brace_nesting--;
119 goto new_statement;
120 }
121 if (token->type == CPP_OPEN_BRACE)
122 {
123 brace_nesting++;
124 goto new_statement;
125 }
126
127 if (token->type == CPP_EOF)
128 return 0;
129
130 if (token->type == CPP_SEMICOLON)
131 goto new_statement;
132 if (token->type != CPP_NAME)
133 goto new_statement;
134
135 prev_id.type = CPP_EOF;
136 for (;;)
137 {
138 switch (token->type)
139 {
140 default:
141 goto handle_statement;
142 case CPP_MULT:
143 case CPP_AND:
144 /* skip */
145 break;
146
147 case CPP_COMMA:
148 case CPP_SEMICOLON:
149 if (prev_id.type != CPP_EOF && saw_extern)
150 {
151 recognized_extern (&prev_id);
152 }
153 if (token->type == CPP_COMMA)
154 break;
155 /* ... fall through ... */
156 case CPP_OPEN_BRACE: case CPP_CLOSE_BRACE:
157 goto new_statement;
158
159 case CPP_EOF:
160 return 0;
161
162 case CPP_OPEN_PAREN:
163 /* Looks like this is the start of a formal parameter list. */
164 if (prev_id.type != CPP_EOF)
165 {
166 int nesting = 1;
167 int have_arg_list = 0;
168 const struct line_map *map;
169 unsigned int line;
170 for (;;)
171 {
172 token = get_a_token (pfile);
173 if (token->type == CPP_OPEN_PAREN)
174 nesting++;
175 else if (token->type == CPP_CLOSE_PAREN)
176 {
177 nesting--;
178 if (nesting == 0)
179 break;
180 }
181 else if (token->type == CPP_EOF)
182 break;
183 else if (token->type == CPP_NAME
184 || token->type == CPP_ELLIPSIS)
185 have_arg_list = 1;
186 }
187 map = linemap_lookup (&line_table, token->src_loc);
188 line = SOURCE_LINE (map, token->src_loc);
189 recognized_function (&prev_id, line,
190 (saw_inline ? 'I'
191 : in_extern_C_brace || current_extern_C
192 ? 'F' : 'f'), have_arg_list);
193 token = get_a_token (pfile);
194 if (token->type == CPP_OPEN_BRACE)
195 {
196 /* skip body of (normally) inline function */
197 skip_to_closing_brace (pfile);
198 goto new_statement;
199 }
200
201 /* skip a possible __attribute__ or throw expression after the
202 parameter list */
203 while (token->type != CPP_SEMICOLON && token->type != CPP_EOF)
204 token = get_a_token (pfile);
205 if (token->type == CPP_EOF)
206 return 0;
207 goto new_statement;
208 }
209 break;
210 case CPP_NAME:
211 /* "inline" and "extern" are recognized but skipped */
212 if (cpp_ideq (token, "inline"))
213 {
214 saw_inline = 1;
215 }
216 else if (cpp_ideq (token, "extern"))
217 {
218 saw_extern = 1;
219 token = get_a_token (pfile);
220 if (token->type == CPP_STRING
221 && token->val.str.len == 1
222 && token->val.str.text[0] == 'C')
223 {
224 current_extern_C = 1;
225 token = get_a_token (pfile);
226 if (token->type == CPP_OPEN_BRACE)
227 {
228 brace_nesting++;
229 extern_C_braces[extern_C_braces_length++]
230 = brace_nesting;
231 if (extern_C_braces_length >= MAX_EXTERN_C_BRACES)
232 {
233 fprintf (stderr,
234 "Internal error: out-of-bounds index\n");
235 exit (FATAL_EXIT_CODE);
236 }
237 goto new_statement;
238 }
239 }
240 else
241 continue;
242 break;
243 }
244 /* This may be the name of a variable or function. */
245 prev_id = *token;
246 break;
247 }
248 token = get_a_token (pfile);
249 }
250 }
251