options.c revision ce377d567ccc0b14693619b69ebe0ac6deb0ba90 
1#if HAVE_CONFIG_H
2#include "config.h"
3#endif
4
5#include <string.h>
6#include <stdlib.h>
7#include <unistd.h>
8#include <fcntl.h>
9#include <errno.h>
10#include <limits.h>
11#include <sys/ioctl.h>
12
13#if HAVE_GETOPT_H
14#include <getopt.h>
15#endif
16
17#include "ltrace.h"
18#include "options.h"
19#include "defs.h"
20
21#ifndef SYSCONFDIR
22#define SYSCONFDIR "/etc"
23#endif
24
25#define SYSTEM_CONFIG_FILE SYSCONFDIR "/ltrace.conf"
26#define USER_CONFIG_FILE "~/.ltrace.conf"
27
28struct options_t options = {
29	.align    = DEFAULT_ALIGN,  /* alignment column for results */
30	.user     = NULL,           /* username to run command as */
31	.syscalls = 0,              /* display syscalls */
32	.libcalls = 1,              /* display library calls */
33#ifdef USE_DEMANGLE
34	.demangle = 0,                 /* Demangle low-level symbol names */
35#endif
36};
37
38#define MAX_LIBRARY		30
39char *library[MAX_LIBRARY];
40int library_num = 0;
41static char *progname;		/* Program name (`ltrace') */
42FILE *output;
43int opt_A = DEFAULT_ARRAYLEN;	/* maximum # array elements to print */
44int opt_c = 0;			/* Report a summary on program exit */
45int opt_d = 0;			/* debug */
46int opt_i = 0;			/* instruction pointer */
47int opt_s = DEFAULT_STRLEN;	/* maximum # of bytes printed in strings */
48int opt_f = 0;			/* trace child processes as they are created */
49int opt_r = 0;			/* print relative timestamp */
50int opt_t = 0;			/* print absolute timestamp */
51int opt_n = 0;			/* indent output according to program flow */
52int opt_T = 0;			/* show the time spent inside each call */
53int opt_o = 0;			/* output to a specific file */
54
55/* List of pids given to option -p: */
56struct opt_p_t *opt_p = NULL;	/* attach to process with a given pid */
57
58/* List of function names given to option -e: */
59struct opt_e_t *opt_e = NULL;
60int opt_e_enable = 1;
61
62/* List of global function names given to -x: */
63struct opt_x_t *opt_x = NULL;
64
65/* List of filenames give to option -F: */
66struct opt_F_t *opt_F = NULL;	/* alternate configuration file(s) */
67
68#ifdef PLT_REINITALISATION_BP
69/* Set a break on the routine named here in order to re-initialize breakpoints
70   after all the PLTs have been initialzed */
71char *PLTs_initialized_by_here = PLT_REINITALISATION_BP;
72#endif
73
74static void
75usage(void) {
76#if !(HAVE_GETOPT || HAVE_GETOPT_LONG)
77	fprintf(stdout, "Usage: %s [command [arg ...]]\n"
78		"Trace library calls of a given program.\n\n", progname);
79#else
80	fprintf(stdout, "Usage: %s [option ...] [command [arg ...]]\n"
81		"Trace library calls of a given program.\n\n"
82# if HAVE_GETOPT_LONG
83		"  -a, --align=COLUMN  align return values in a secific column.\n"
84# else
85		"  -a COLUMN           align return values in a secific column.\n"
86# endif
87		"  -A ARRAYLEN         maximum number of array elements to print.\n"
88		"  -c                  count time and calls, and report a summary on exit.\n"
89# ifdef USE_DEMANGLE
90#  if HAVE_GETOPT_LONG
91		"  -C, --demangle      decode low-level symbol names into user-level names.\n"
92#  else
93		"  -C                  decode low-level symbol names into user-level names.\n"
94#  endif
95# endif
96# if HAVE_GETOPT_LONG
97		"  -d, --debug         print debugging info.\n"
98# else
99		"  -d                  print debugging info.\n"
100# endif
101		"  -e expr             modify which events to trace.\n"
102		"  -f                  follow forks.\n"
103# if HAVE_GETOPT_LONG
104		"  -F, --config=FILE   load alternate configuration file (can be repeated).\n"
105# else
106		"  -F FILE             load alternate configuration file (can be repeated).\n"
107# endif
108# if HAVE_GETOPT_LONG
109		"  -h, --help          display this help and exit.\n"
110# else
111		"  -h                  display this help and exit.\n"
112# endif
113		"  -i                  print instruction pointer at time of library call.\n"
114#  if HAVE_GETOPT_LONG
115		"  -l, --library=FILE  print library calls from this library only.\n"
116#  else
117		"  -l FILE             print library calls from this library only.\n"
118#  endif
119		"  -L                  do NOT display library calls.\n"
120# if HAVE_GETOPT_LONG
121		"  -n, --indent=NR     indent output by NR spaces for each call level nesting.\n"
122# else
123		"  -n NR               indent output by NR spaces for each call level nesting.\n"
124# endif
125# if HAVE_GETOPT_LONG
126		"  -o, --output=FILE   write the trace output to that file.\n"
127# else
128		"  -o FILE             write the trace output to that file.\n"
129# endif
130		"  -p PID              attach to the process with the process ID pid.\n"
131		"  -r                  print relative timestamps.\n"
132		"  -s STRLEN           specify the maximum string size to print.\n"
133		"  -S                  display system calls.\n"
134		"  -t, -tt, -ttt       print absolute timestamps.\n"
135		"  -T                  show the time spent inside each call.\n"
136		"  -u USERNAME         run command with the userid, groupid of username.\n"
137# if HAVE_GETOPT_LONG
138		"  -V, --version       output version information and exit.\n"
139# else
140		"  -V                  output version information and exit.\n"
141# endif
142		"  -x NAME             treat the global NAME like a library subroutine.\n"
143#ifdef PLT_REINITALISATION_BP
144		"  -X NAME             same as -x; and PLT's will be initialized by here.\n"
145#endif
146		"\nReport bugs to ltrace-devel@lists.alioth.debian.org\n",
147		progname);
148#endif
149}
150
151static char *
152search_for_command(char *filename) {
153	static char pathname[PATH_MAX];
154	char *path;
155	int m, n;
156
157	if (strchr(filename, '/')) {
158		return filename;
159	}
160	for (path = getenv("PATH"); path && *path; path += m) {
161		if (strchr(path, ':')) {
162			n = strchr(path, ':') - path;
163			m = n + 1;
164		} else {
165			m = n = strlen(path);
166		}
167		if (n + strlen(filename) + 1 >= PATH_MAX) {
168			fprintf(stderr, "Error: filename too long\n");
169			exit(1);
170		}
171		strncpy(pathname, path, n);
172		if (n && pathname[n - 1] != '/') {
173			pathname[n++] = '/';
174		}
175		strcpy(pathname + n, filename);
176		if (!access(pathname, X_OK)) {
177			return pathname;
178		}
179	}
180	return filename;
181}
182
183static void
184guess_cols(void) {
185	struct winsize ws;
186	char *c;
187
188	options.align = DEFAULT_ALIGN;
189	c = getenv("COLUMNS");
190	if (c && *c) {
191		char *endptr;
192		int cols;
193		cols = strtol(c, &endptr, 0);
194		if (cols > 0 && !*endptr) {
195			options.align = cols * 5 / 8;
196		}
197	} else if (ioctl(1, TIOCGWINSZ, &ws) != -1 && ws.ws_col > 0) {
198		options.align = ws.ws_col * 5 / 8;
199	}
200}
201
202char **
203process_options(int argc, char **argv) {
204	progname = argv[0];
205	output = stderr;
206
207	guess_cols();
208
209#if HAVE_GETOPT || HAVE_GETOPT_LONG
210	while (1) {
211		int c;
212#if HAVE_GETOPT_LONG
213		int option_index = 0;
214		static struct option long_options[] = {
215			{"align", 1, 0, 'a'},
216			{"config", 1, 0, 'F'},
217			{"debug", 0, 0, 'd'},
218# ifdef USE_DEMANGLE
219			{"demangle", 0, 0, 'C'},
220#endif
221			{"indent", 1, 0, 'n'},
222			{"help", 0, 0, 'h'},
223			{"library", 1, 0, 'l'},
224			{"output", 1, 0, 'o'},
225			{"version", 0, 0, 'V'},
226			{0, 0, 0, 0}
227		};
228		c = getopt_long(argc, argv, "+cdfhiLrStTV"
229# ifdef USE_DEMANGLE
230				"C"
231# endif
232				"a:A:e:F:l:n:o:p:s:u:x:X:", long_options,
233				&option_index);
234#else
235		c = getopt(argc, argv, "+cdfhiLrStTV"
236# ifdef USE_DEMANGLE
237				"C"
238# endif
239				"a:A:e:F:l:n:o:p:s:u:x:X:");
240#endif
241		if (c == -1) {
242			break;
243		}
244		switch (c) {
245		case 'a':
246			options.align = atoi(optarg);
247			break;
248		case 'A':
249			opt_A = atoi(optarg);
250			break;
251		case 'c':
252			opt_c++;
253			break;
254#ifdef USE_DEMANGLE
255		case 'C':
256			options.demangle++;
257			break;
258#endif
259		case 'd':
260			opt_d++;
261			break;
262		case 'e':
263			{
264				char *str_e = strdup(optarg);
265				if (!str_e) {
266					perror("ltrace: strdup");
267					exit(1);
268				}
269				if (str_e[0] == '!') {
270					opt_e_enable = 0;
271					str_e++;
272				}
273				while (*str_e) {
274					struct opt_e_t *tmp;
275					char *str2 = strchr(str_e, ',');
276					if (str2) {
277						*str2 = '\0';
278					}
279					tmp = malloc(sizeof(struct opt_e_t));
280					if (!tmp) {
281						perror("ltrace: malloc");
282						exit(1);
283					}
284					tmp->name = str_e;
285					tmp->next = opt_e;
286					opt_e = tmp;
287					if (str2) {
288						str_e = str2 + 1;
289					} else {
290						break;
291					}
292				}
293				break;
294			}
295		case 'f':
296			opt_f = 1;
297			break;
298		case 'F':
299			{
300				struct opt_F_t *tmp = malloc(sizeof(struct opt_F_t));
301				if (!tmp) {
302					perror("ltrace: malloc");
303					exit(1);
304				}
305				tmp->filename = strdup(optarg);
306				tmp->next = opt_F;
307				opt_F = tmp;
308				break;
309			}
310		case 'h':
311			usage();
312			exit(0);
313		case 'i':
314			opt_i++;
315			break;
316		case 'l':
317			if (library_num == MAX_LIBRARY) {
318				fprintf(stderr,
319					"Too many libraries.  Maximum is %i.\n",
320					MAX_LIBRARY);
321				exit(1);
322			}
323			library[library_num++] = optarg;
324			break;
325		case 'L':
326			options.libcalls = 0;
327			break;
328		case 'n':
329			opt_n = atoi(optarg);
330			break;
331		case 'o':
332			opt_o++;
333			output = fopen(optarg, "w");
334			if (!output) {
335				fprintf(stderr,
336					"Can't open %s for output: %s\n",
337					optarg, strerror(errno));
338				exit(1);
339			}
340			setvbuf(output, (char *)NULL, _IOLBF, 0);
341			fcntl(fileno(output), F_SETFD, FD_CLOEXEC);
342			break;
343		case 'p':
344			{
345				struct opt_p_t *tmp = malloc(sizeof(struct opt_p_t));
346				if (!tmp) {
347					perror("ltrace: malloc");
348					exit(1);
349				}
350				tmp->pid = atoi(optarg);
351				tmp->next = opt_p;
352				opt_p = tmp;
353				break;
354			}
355		case 'r':
356			opt_r++;
357			break;
358		case 's':
359			opt_s = atoi(optarg);
360			break;
361		case 'S':
362			options.syscalls = 1;
363			break;
364		case 't':
365			opt_t++;
366			break;
367		case 'T':
368			opt_T++;
369			break;
370		case 'u':
371			options.user = optarg;
372			break;
373		case 'V':
374			printf("ltrace version " PACKAGE_VERSION ".\n"
375					"Copyright (C) 1997-2008 Juan Cespedes <cespedes@debian.org>.\n"
376					"This is free software; see the GNU General Public Licence\n"
377					"version 2 or later for copying conditions.  There is NO warranty.\n");
378			exit(0);
379		case 'X':
380#ifdef PLT_REINITALISATION_BP
381			PLTs_initialized_by_here = optarg;
382#else
383			fprintf(stderr, "WARNING: \"-X\" not used for this "
384				"architecture: assuming you meant \"-x\"\n");
385#endif
386			/* Fall Thru */
387
388		case 'x':
389			{
390				struct opt_x_t *p = opt_x;
391
392				/* First, check for duplicate. */
393				while (p && strcmp(p->name, optarg)) {
394					p = p->next;
395				}
396				if (p) {
397					break;
398				}
399
400				/* If not duplicate, add to list. */
401				p = malloc(sizeof(struct opt_x_t));
402				if (!p) {
403					perror("ltrace: malloc");
404					exit(1);
405				}
406				p->name = optarg;
407				p->found = 0;
408				p->next = opt_x;
409				opt_x = p;
410				break;
411			}
412
413		default:
414#if HAVE_GETOPT_LONG
415			fprintf(stderr,
416				"Try `%s --help' for more information\n",
417				progname);
418#else
419			fprintf(stderr, "Try `%s -h' for more information\n",
420				progname);
421#endif
422			exit(1);
423		}
424	}
425	argc -= optind;
426	argv += optind;
427#endif
428
429	if (!opt_F) {
430		opt_F = malloc(sizeof(struct opt_F_t));
431		opt_F->next = malloc(sizeof(struct opt_F_t));
432		opt_F->next->next = NULL;
433		opt_F->filename = USER_CONFIG_FILE;
434		opt_F->next->filename = SYSTEM_CONFIG_FILE;
435	}
436	/* Reverse the config file list since it was built by
437	 * prepending, and it would make more sense to process the
438	 * files in the order they were given. Probably it would make
439	 * more sense to keep a tail pointer instead? */
440	{
441		struct opt_F_t *egg = NULL;
442		struct opt_F_t *chicken;
443		while (opt_F) {
444			chicken = opt_F->next;
445			opt_F->next = egg;
446			egg = opt_F;
447			opt_F = chicken;
448		}
449		opt_F = egg;
450	}
451
452	if (!opt_p && argc < 1) {
453		fprintf(stderr, "%s: too few arguments\n", progname);
454		usage();
455		exit(1);
456	}
457	if (opt_r && opt_t) {
458		fprintf(stderr, "%s: Incompatible options -r and -t\n",
459			progname);
460		exit(1);
461	}
462	if (argc > 0) {
463		command = search_for_command(argv[0]);
464	}
465	return &argv[0];
466}
467