Add comment to clarify how the test can fail
[glibc.git] / debug / pcprofiledump.c
blobb6954a71cd35be00ea77fb085919fe4e4c34b6fc
1 /* Dump information generated by PC profiling.
2 Copyright (C) 1999-2015 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1999.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
20 /* This is mainly an example. It shows how programs which want to use
21 the information should read the file. */
22 #ifdef HAVE_CONFIG_H
23 # include <config.h>
24 #endif
26 #include <argp.h>
27 #include <byteswap.h>
28 #include <errno.h>
29 #include <error.h>
30 #include <fcntl.h>
31 #include <inttypes.h>
32 #include <libintl.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <unistd.h>
36 #include <stdint.h>
38 #include "../version.h"
40 #define PACKAGE _libc_intl_domainname
42 #ifndef _
43 # define _(Str) gettext (Str)
44 #endif
46 #ifndef N_
47 # define N_(Str) Str
48 #endif
50 /* Definitions of arguments for argp functions. */
51 static const struct argp_option options[] =
53 { "unbuffered", 'u', NULL, 0, N_("Don't buffer output") },
54 { NULL, 0, NULL, 0, NULL }
57 /* Short description of program. */
58 static const char doc[] = N_("Dump information generated by PC profiling.");
60 /* Strings for arguments in help texts. */
61 static const char args_doc[] = N_("[FILE]");
63 /* Function to print some extra text in the help message. */
64 static char *more_help (int key, const char *text, void *input);
66 /* Prototype for option handler. */
67 static error_t parse_opt (int key, char *arg, struct argp_state *state);
69 /* Name and version of program. */
70 static void print_version (FILE *stream, struct argp_state *state);
71 void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;
73 /* Data structure to communicate with argp functions. */
74 static struct argp argp =
76 options, parse_opt, args_doc, doc, NULL, more_help
80 int
81 main (int argc, char *argv[])
83 /* Set locale via LC_ALL. */
84 setlocale (LC_ALL, "");
86 /* Set the text message domain. */
87 textdomain (PACKAGE);
89 /* Parse and process arguments. */
90 int remaining;
91 argp_parse (&argp, argc, argv, 0, &remaining, NULL);
93 int fd;
94 if (remaining == argc)
95 fd = STDIN_FILENO;
96 else if (remaining + 1 != argc)
98 argp_help (&argp, stdout, ARGP_HELP_SEE | ARGP_HELP_EXIT_ERR,
99 program_invocation_short_name);
100 exit (1);
102 else
104 /* Open the given file. */
105 fd = open (argv[remaining], O_RDONLY);
107 if (fd == -1)
108 error (EXIT_FAILURE, errno, _("cannot open input file"));
111 /* Read the first 4-byte word. It contains the information about
112 the word size and the endianess. */
113 uint32_t word;
114 if (TEMP_FAILURE_RETRY (read (fd, &word, 4)) != 4)
115 error (EXIT_FAILURE, errno, _("cannot read header"));
117 /* Check whether we have to swap the byte order. */
118 int must_swap = (word & 0xfffffff0) == bswap_32 (0xdeb00000);
119 if (must_swap)
120 word = bswap_32 (word);
122 /* We have two loops, one for 32 bit pointers, one for 64 bit pointers. */
123 if (word == 0xdeb00004)
125 union
127 uint32_t ptrs[2];
128 char bytes[8];
129 } pair;
131 while (1)
133 size_t len = sizeof (pair);
134 size_t n;
136 while (len > 0
137 && (n = TEMP_FAILURE_RETRY (read (fd, &pair.bytes[8 - len],
138 len))) != 0)
139 len -= n;
141 if (len != 0)
142 /* Nothing to read. */
143 break;
145 printf ("this = %#010" PRIx32 ", caller = %#010" PRIx32 "\n",
146 must_swap ? bswap_32 (pair.ptrs[0]) : pair.ptrs[0],
147 must_swap ? bswap_32 (pair.ptrs[1]) : pair.ptrs[1]);
150 else if (word == 0xdeb00008)
152 union
154 uint64_t ptrs[2];
155 char bytes[16];
156 } pair;
158 while (1)
160 size_t len = sizeof (pair);
161 size_t n;
163 while (len > 0
164 && (n = TEMP_FAILURE_RETRY (read (fd, &pair.bytes[8 - len],
165 len))) != 0)
166 len -= n;
168 if (len != 0)
169 /* Nothing to read. */
170 break;
172 printf ("this = %#018" PRIx64 ", caller = %#018" PRIx64 "\n",
173 must_swap ? bswap_64 (pair.ptrs[0]) : pair.ptrs[0],
174 must_swap ? bswap_64 (pair.ptrs[1]) : pair.ptrs[1]);
177 else
178 /* This should not happen. */
179 error (EXIT_FAILURE, 0, _("invalid pointer size"));
181 /* Clean up. */
182 close (fd);
184 return 0;
187 static error_t
188 parse_opt (int key, char *arg, struct argp_state *state)
190 switch (key)
192 case 'u':
193 setbuf (stdout, NULL);
194 break;
195 default:
196 return ARGP_ERR_UNKNOWN;
198 return 0;
201 static char *
202 more_help (int key, const char *text, void *input)
204 char *tp = NULL;
205 switch (key)
207 case ARGP_KEY_HELP_EXTRA:
208 /* We print some extra information. */
209 if (asprintf (&tp, gettext ("\
210 For bug reporting instructions, please see:\n\
211 %s.\n"), REPORT_BUGS_TO) < 0)
212 return NULL;
213 return tp;
214 default:
215 break;
217 return (char *) text;
220 /* Print the version information. */
221 static void
222 print_version (FILE *stream, struct argp_state *state)
224 fprintf (stream, "pcprofiledump %s%s\n", PKGVERSION, VERSION);
225 fprintf (stream, gettext ("\
226 Copyright (C) %s Free Software Foundation, Inc.\n\
227 This is free software; see the source for copying conditions. There is NO\n\
228 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
229 "), "2015");
230 fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");