GCC Middle and Back End API Reference
collect2-aix.h
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1 /* AIX cross support for collect2.
2  Copyright (C) 2009-2013 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10 
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19 
20 /* collect2-aix.c requires mmap support. It should otherwise be
21  fairly portable. */
22 #if defined(CROSS_DIRECTORY_STRUCTURE) \
23  && defined(TARGET_AIX_VERSION) \
24  && HAVE_MMAP
25 
26 #define CROSS_AIX_SUPPORT 1
27 
28 /* -------------------------------------------------------------------------
29  Definitions adapted from bfd. (Fairly heavily adapted in some cases.)
30  ------------------------------------------------------------------------- */
31 
32 /* Compatibility types for bfd. */
33 typedef unsigned HOST_WIDE_INT bfd_vma;
34 
35 /* The size of an archive's fl_magic field. */
36 #define FL_MAGIC_SIZE 8
37 
38 /* The expected contents of fl_magic for big archives. */
39 #define FL_MAGIC_BIG_AR "<bigaf>\012"
40 
41 /* The size of each offset string in the header of a big archive. */
42 #define AR_BIG_OFFSET_SIZE 20
43 
44 /* The format of the file header in a "big" XCOFF archive. */
45 struct external_big_ar_filehdr
46 {
47  /* Magic string. */
48  char fl_magic[FL_MAGIC_SIZE];
49 
50  /* Offset of the member table (decimal ASCII string). */
51  char fl_memoff[AR_BIG_OFFSET_SIZE];
52 
53  /* Offset of the global symbol table for 32-bit objects (decimal ASCII
54  string). */
55  char fl_symoff[AR_BIG_OFFSET_SIZE];
56 
57  /* Offset of the global symbol table for 64-bit objects (decimal ASCII
58  string). */
59  char fl_symoff64[AR_BIG_OFFSET_SIZE];
60 
61  /* Offset of the first member in the archive (decimal ASCII string). */
62  char fl_firstmemoff[AR_BIG_OFFSET_SIZE];
63 
64  /* Offset of the last member in the archive (decimal ASCII string). */
65  char fl_lastmemoff[AR_BIG_OFFSET_SIZE];
66 
67  /* Offset of the first member on the free list (decimal ASCII
68  string). */
69  char fl_freeoff[AR_BIG_OFFSET_SIZE];
70 };
71 
72 /* Each archive name is followed by this many bytes of magic string. */
73 #define SXCOFFARFMAG 2
74 
75 /* The format of a member header in a "big" XCOFF archive. */
76 struct external_big_ar_member
77 {
78  /* File size not including the header (decimal ASCII string). */
79  char ar_size[AR_BIG_OFFSET_SIZE];
80 
81  /* File offset of next archive member (decimal ASCII string). */
82  char ar_nextoff[AR_BIG_OFFSET_SIZE];
83 
84  /* File offset of previous archive member (decimal ASCII string). */
85  char ar_prevoff[AR_BIG_OFFSET_SIZE];
86 
87  /* File mtime (decimal ASCII string). */
88  char ar_date[12];
89 
90  /* File UID (decimal ASCII string). */
91  char ar_uid[12];
92 
93  /* File GID (decimal ASCII string). */
94  char ar_gid[12];
95 
96  /* File mode (octal ASCII string). */
97  char ar_mode[12];
98 
99  /* Length of file name (decimal ASCII string). */
100  char ar_namlen[4];
101 
102  /* This structure is followed by the file name. The length of the
103  name is given in the namlen field. If the length of the name is
104  odd, the name is followed by a null byte. The name and optional
105  null byte are followed by XCOFFARFMAG, which is not included in
106  namlen. The contents of the archive member follow; the number of
107  bytes is given in the size field. */
108 };
109 
110 /* The known values of f_magic in an XCOFF file header. */
111 #define U802WRMAGIC 0730 /* Writeable text segments. */
112 #define U802ROMAGIC 0735 /* Readonly sharable text segments. */
113 #define U802TOCMAGIC 0737 /* Readonly text segments and TOC. */
114 #define U803XTOCMAGIC 0757 /* Aix 4.3 64-bit XCOFF. */
115 #define U64_TOCMAGIC 0767 /* AIX 5+ 64-bit XCOFF. */
116 
117 /* The number of bytes in an XCOFF file's f_magic field. */
118 #define F_MAGIC_SIZE 2
119 
120 /* The format of a 32-bit XCOFF file header. */
121 struct external_filehdr_32
122 {
123  /* The magic number. */
124  char f_magic[F_MAGIC_SIZE];
125 
126  /* The number of sections. */
127  char f_nscns[2];
128 
129  /* Time & date stamp. */
130  char f_timdat[4];
131 
132  /* The offset of the symbol table from the start of the file. */
133  char f_symptr[4];
134 
135  /* The number of entries in the symbol table. */
136  char f_nsyms[4];
137 
138  /* The size of the auxiliary header. */
139  char f_opthdr[2];
140 
141  /* Flags. */
142  char f_flags[2];
143 };
144 
145 /* The format of a 64-bit XCOFF file header. */
146 struct external_filehdr_64
147 {
148  /* The magic number. */
149  char f_magic[F_MAGIC_SIZE];
150 
151  /* The number of sections. */
152  char f_nscns[2];
153 
154  /* Time & date stamp. */
155  char f_timdat[4];
156 
157  /* The offset of the symbol table from the start of the file. */
158  char f_symptr[8];
159 
160  /* The size of the auxiliary header. */
161  char f_opthdr[2];
162 
163  /* Flags. */
164  char f_flags[2];
165 
166  /* The number of entries in the symbol table. */
167  char f_nsyms[4];
168 };
169 
170 /* An internal representation of the XCOFF file header. */
171 struct internal_filehdr
172 {
173  unsigned short f_magic;
174  unsigned short f_nscns;
175  long f_timdat;
176  bfd_vma f_symptr;
177  long f_nsyms;
178  unsigned short f_opthdr;
179  unsigned short f_flags;
180 };
181 
182 /* Symbol classes have their names in the debug section if this flag
183  is set. */
184 #define DBXMASK 0x80
185 
186 /* The format of an XCOFF symbol-table entry. */
187 struct external_syment
188 {
189  union {
190  struct {
191  union {
192  /* The name of the symbol. There is an implicit null character
193  after the end of the array. */
194  char n_name[8];
195  struct {
196  /* If n_zeroes is zero, n_offset is the offset the name from
197  the start of the string table. */
198  char n_zeroes[4];
199  char n_offset[4];
200  } u;
201  } u;
202 
203  /* The symbol's value. */
204  char n_value[4];
205  } xcoff32;
206  struct {
207  /* The symbol's value. */
208  char n_value[8];
209 
210  /* The offset of the symbol from the start of the string table. */
211  char n_offset[4];
212  } xcoff64;
213  } u;
214 
215  /* The number of the section to which this symbol belongs. */
216  char n_scnum[2];
217 
218  /* The type of symbol. (It can be interpreted as an n_lang
219  and an n_cpu byte, but we don't care about that here.) */
220  char n_type[2];
221 
222  /* The class of symbol (a C_* value). */
223  char n_sclass[1];
224 
225  /* The number of auxiliary symbols attached to this entry. */
226  char n_numaux[1];
227 };
228 
229 /* Definitions required by collect2. */
230 #define C_EXT 2
231 
232 #define F_SHROBJ 0x2000
233 #define F_LOADONLY 0x4000
234 
235 #define N_UNDEF ((short) 0)
236 #define N_TMASK 060
237 #define N_BTSHFT 4
238 
239 #define DT_NON 0
240 #define DT_FCN 2
241 
242 /* -------------------------------------------------------------------------
243  Local code.
244  ------------------------------------------------------------------------- */
245 
246 /* An internal representation of an XCOFF symbol-table entry,
247  which is associated with the API-defined SYMENT type. */
248 struct internal_syment
249 {
250  char n_name[9];
251  unsigned int n_zeroes;
252  bfd_vma n_offset;
253  bfd_vma n_value;
254  short n_scnum;
255  unsigned short n_flags;
256  unsigned short n_type;
257  unsigned char n_sclass;
258  unsigned char n_numaux;
259 };
260 typedef struct internal_syment SYMENT;
261 
262 /* The internal representation of the API-defined LDFILE type. */
263 struct internal_ldfile
264 {
265  /* The file handle for the associated file, or -1 if it hasn't been
266  opened yet. */
267  int fd;
268 
269  /* The start of the current XCOFF object, if one has been mapped
270  into memory. Null otherwise. */
271  char *object;
272 
273  /* The offset of OBJECT from the start of the containing page. */
274  size_t page_offset;
275 
276  /* The size of the file pointed to by OBJECT. Valid iff OFFSET
277  is nonnull. */
278  size_t object_size;
279 
280  /* The offset of the next member in an archive after OBJECT,
281  or -1 if this isn't an archive. Valid iff OFFSET is nonnull. */
282  off_t next_member;
283 
284  /* The parsed version of the XCOFF file header. */
285  struct internal_filehdr filehdr;
286 };
287 typedef struct internal_ldfile LDFILE;
288 
289 /* The API allows the file header to be directly accessed via this macro. */
290 #define HEADER(FILE) ((FILE)->filehdr)
291 
292 /* API-defined return codes. SUCCESS must be > 0 and FAILURE must be <= 0. */
293 #define SUCCESS 1
294 #define FAILURE 0
295 
296 /* API-defined functions. */
297 extern LDFILE *ldopen (char *, LDFILE *);
298 extern char *ldgetname (LDFILE *, SYMENT *);
299 extern int ldtbread (LDFILE *, long, SYMENT *);
300 extern int ldclose (LDFILE *);
301 
302 #endif