1 /*
2 * recordmcount.c: construct a table of the locations of calls to 'mcount'
3 * so that ftrace can find them quickly.
4 * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved.
5 * Licensed under the GNU General Public License, version 2 (GPLv2).
6 *
7 * Restructured to fit Linux format, as well as other updates:
8 * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
9 */
10
11 /*
12 * Strategy: alter the .o file in-place.
13 *
14 * Append a new STRTAB that has the new section names, followed by a new array
15 * ElfXX_Shdr[] that has the new section headers, followed by the section
16 * contents for __mcount_loc and its relocations. The old shstrtab strings,
17 * and the old ElfXX_Shdr[] array, remain as "garbage" (commonly, a couple
18 * kilobytes.) Subsequent processing by /bin/ld (or the kernel module loader)
19 * will ignore the garbage regions, because they are not designated by the
20 * new .e_shoff nor the new ElfXX_Shdr[]. [In order to remove the garbage,
21 * then use "ld -r" to create a new file that omits the garbage.]
22 */
23
24 #include <sys/types.h>
25 #include <sys/mman.h>
26 #include <sys/stat.h>
27 #include <getopt.h>
28 #include <elf.h>
29 #include <fcntl.h>
30 #include <setjmp.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <unistd.h>
35
36 #ifndef EM_AARCH64
37 #define EM_AARCH64 183
38 #define R_AARCH64_NONE 0
39 #define R_AARCH64_ABS64 257
40 #endif
41
42 #define R_ARM_PC24 1
43 #define R_ARM_THM_CALL 10
44 #define R_ARM_CALL 28
45
46 static int fd_map; /* File descriptor for file being modified. */
47 static int mmap_failed; /* Boolean flag. */
48 static char gpfx; /* prefix for global symbol name (sometimes '_') */
49 static struct stat sb; /* Remember .st_size, etc. */
50 static jmp_buf jmpenv; /* setjmp/longjmp per-file error escape */
51 static const char *altmcount; /* alternate mcount symbol name */
52 static int warn_on_notrace_sect; /* warn when section has mcount not being recorded */
53 static void *file_map; /* pointer of the mapped file */
54 static void *file_end; /* pointer to the end of the mapped file */
55 static int file_updated; /* flag to state file was changed */
56 static void *file_ptr; /* current file pointer location */
57 static void *file_append; /* added to the end of the file */
58 static size_t file_append_size; /* how much is added to end of file */
59
60 /* setjmp() return values */
61 enum {
62 SJ_SETJMP = 0, /* hardwired first return */
63 SJ_FAIL,
64 SJ_SUCCEED
65 };
66
67 /* Per-file resource cleanup when multiple files. */
68 static void
cleanup(void)69 cleanup(void)
70 {
71 if (!mmap_failed)
72 munmap(file_map, sb.st_size);
73 else
74 free(file_map);
75 file_map = NULL;
76 free(file_append);
77 file_append = NULL;
78 file_append_size = 0;
79 file_updated = 0;
80 }
81
82 static void __attribute__((noreturn))
fail_file(void)83 fail_file(void)
84 {
85 cleanup();
86 longjmp(jmpenv, SJ_FAIL);
87 }
88
89 static void __attribute__((noreturn))
succeed_file(void)90 succeed_file(void)
91 {
92 cleanup();
93 longjmp(jmpenv, SJ_SUCCEED);
94 }
95
96 /* ulseek, uread, ...: Check return value for errors. */
97
98 static off_t
ulseek(int const fd,off_t const offset,int const whence)99 ulseek(int const fd, off_t const offset, int const whence)
100 {
101 switch (whence) {
102 case SEEK_SET:
103 file_ptr = file_map + offset;
104 break;
105 case SEEK_CUR:
106 file_ptr += offset;
107 break;
108 case SEEK_END:
109 file_ptr = file_map + (sb.st_size - offset);
110 break;
111 }
112 if (file_ptr < file_map) {
113 fprintf(stderr, "lseek: seek before file\n");
114 fail_file();
115 }
116 return file_ptr - file_map;
117 }
118
119 static size_t
uread(int const fd,void * const buf,size_t const count)120 uread(int const fd, void *const buf, size_t const count)
121 {
122 size_t const n = read(fd, buf, count);
123 if (n != count) {
124 perror("read");
125 fail_file();
126 }
127 return n;
128 }
129
130 static size_t
uwrite(int const fd,void const * const buf,size_t const count)131 uwrite(int const fd, void const *const buf, size_t const count)
132 {
133 size_t cnt = count;
134 off_t idx = 0;
135
136 file_updated = 1;
137
138 if (file_ptr + count >= file_end) {
139 off_t aoffset = (file_ptr + count) - file_end;
140
141 if (aoffset > file_append_size) {
142 file_append = realloc(file_append, aoffset);
143 file_append_size = aoffset;
144 }
145 if (!file_append) {
146 perror("write");
147 fail_file();
148 }
149 if (file_ptr < file_end) {
150 cnt = file_end - file_ptr;
151 } else {
152 cnt = 0;
153 idx = aoffset - count;
154 }
155 }
156
157 if (cnt)
158 memcpy(file_ptr, buf, cnt);
159
160 if (cnt < count)
161 memcpy(file_append + idx, buf + cnt, count - cnt);
162
163 file_ptr += count;
164 return count;
165 }
166
167 static void *
umalloc(size_t size)168 umalloc(size_t size)
169 {
170 void *const addr = malloc(size);
171 if (addr == 0) {
172 fprintf(stderr, "malloc failed: %zu bytes\n", size);
173 fail_file();
174 }
175 return addr;
176 }
177
178 static unsigned char ideal_nop5_x86_64[5] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 };
179 static unsigned char ideal_nop5_x86_32[5] = { 0x3e, 0x8d, 0x74, 0x26, 0x00 };
180 static unsigned char *ideal_nop;
181
182 static char rel_type_nop;
183
184 static int (*make_nop)(void *map, size_t const offset);
185
make_nop_x86(void * map,size_t const offset)186 static int make_nop_x86(void *map, size_t const offset)
187 {
188 uint32_t *ptr;
189 unsigned char *op;
190
191 /* Confirm we have 0xe8 0x0 0x0 0x0 0x0 */
192 ptr = map + offset;
193 if (*ptr != 0)
194 return -1;
195
196 op = map + offset - 1;
197 if (*op != 0xe8)
198 return -1;
199
200 /* convert to nop */
201 ulseek(fd_map, offset - 1, SEEK_SET);
202 uwrite(fd_map, ideal_nop, 5);
203 return 0;
204 }
205
206 static unsigned char ideal_nop4_arm_le[4] = { 0x00, 0x00, 0xa0, 0xe1 }; /* mov r0, r0 */
207 static unsigned char ideal_nop4_arm_be[4] = { 0xe1, 0xa0, 0x00, 0x00 }; /* mov r0, r0 */
208 static unsigned char *ideal_nop4_arm;
209
210 static unsigned char bl_mcount_arm_le[4] = { 0xfe, 0xff, 0xff, 0xeb }; /* bl */
211 static unsigned char bl_mcount_arm_be[4] = { 0xeb, 0xff, 0xff, 0xfe }; /* bl */
212 static unsigned char *bl_mcount_arm;
213
214 static unsigned char push_arm_le[4] = { 0x04, 0xe0, 0x2d, 0xe5 }; /* push {lr} */
215 static unsigned char push_arm_be[4] = { 0xe5, 0x2d, 0xe0, 0x04 }; /* push {lr} */
216 static unsigned char *push_arm;
217
218 static unsigned char ideal_nop2_thumb_le[2] = { 0x00, 0xbf }; /* nop */
219 static unsigned char ideal_nop2_thumb_be[2] = { 0xbf, 0x00 }; /* nop */
220 static unsigned char *ideal_nop2_thumb;
221
222 static unsigned char push_bl_mcount_thumb_le[6] = { 0x00, 0xb5, 0xff, 0xf7, 0xfe, 0xff }; /* push {lr}, bl */
223 static unsigned char push_bl_mcount_thumb_be[6] = { 0xb5, 0x00, 0xf7, 0xff, 0xff, 0xfe }; /* push {lr}, bl */
224 static unsigned char *push_bl_mcount_thumb;
225
make_nop_arm(void * map,size_t const offset)226 static int make_nop_arm(void *map, size_t const offset)
227 {
228 char *ptr;
229 int cnt = 1;
230 int nop_size;
231 size_t off = offset;
232
233 ptr = map + offset;
234 if (memcmp(ptr, bl_mcount_arm, 4) == 0) {
235 if (memcmp(ptr - 4, push_arm, 4) == 0) {
236 off -= 4;
237 cnt = 2;
238 }
239 ideal_nop = ideal_nop4_arm;
240 nop_size = 4;
241 } else if (memcmp(ptr - 2, push_bl_mcount_thumb, 6) == 0) {
242 cnt = 3;
243 nop_size = 2;
244 off -= 2;
245 ideal_nop = ideal_nop2_thumb;
246 } else
247 return -1;
248
249 /* Convert to nop */
250 ulseek(fd_map, off, SEEK_SET);
251
252 do {
253 uwrite(fd_map, ideal_nop, nop_size);
254 } while (--cnt > 0);
255
256 return 0;
257 }
258
259 static unsigned char ideal_nop4_arm64[4] = {0x1f, 0x20, 0x03, 0xd5};
make_nop_arm64(void * map,size_t const offset)260 static int make_nop_arm64(void *map, size_t const offset)
261 {
262 uint32_t *ptr;
263
264 ptr = map + offset;
265 /* bl <_mcount> is 0x94000000 before relocation */
266 if (*ptr != 0x94000000)
267 return -1;
268
269 /* Convert to nop */
270 ulseek(fd_map, offset, SEEK_SET);
271 uwrite(fd_map, ideal_nop, 4);
272 return 0;
273 }
274
275 /*
276 * Get the whole file as a programming convenience in order to avoid
277 * malloc+lseek+read+free of many pieces. If successful, then mmap
278 * avoids copying unused pieces; else just read the whole file.
279 * Open for both read and write; new info will be appended to the file.
280 * Use MAP_PRIVATE so that a few changes to the in-memory ElfXX_Ehdr
281 * do not propagate to the file until an explicit overwrite at the last.
282 * This preserves most aspects of consistency (all except .st_size)
283 * for simultaneous readers of the file while we are appending to it.
284 * However, multiple writers still are bad. We choose not to use
285 * locking because it is expensive and the use case of kernel build
286 * makes multiple writers unlikely.
287 */
mmap_file(char const * fname)288 static void *mmap_file(char const *fname)
289 {
290 fd_map = open(fname, O_RDONLY);
291 if (fd_map < 0 || fstat(fd_map, &sb) < 0) {
292 perror(fname);
293 fail_file();
294 }
295 if (!S_ISREG(sb.st_mode)) {
296 fprintf(stderr, "not a regular file: %s\n", fname);
297 fail_file();
298 }
299 file_map = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE,
300 fd_map, 0);
301 mmap_failed = 0;
302 if (file_map == MAP_FAILED) {
303 mmap_failed = 1;
304 file_map = umalloc(sb.st_size);
305 uread(fd_map, file_map, sb.st_size);
306 }
307 close(fd_map);
308
309 file_end = file_map + sb.st_size;
310
311 return file_map;
312 }
313
write_file(const char * fname)314 static void write_file(const char *fname)
315 {
316 char tmp_file[strlen(fname) + 4];
317 size_t n;
318
319 if (!file_updated)
320 return;
321
322 sprintf(tmp_file, "%s.rc", fname);
323
324 /*
325 * After reading the entire file into memory, delete it
326 * and write it back, to prevent weird side effects of modifying
327 * an object file in place.
328 */
329 fd_map = open(tmp_file, O_WRONLY | O_TRUNC | O_CREAT, sb.st_mode);
330 if (fd_map < 0) {
331 perror(fname);
332 fail_file();
333 }
334 n = write(fd_map, file_map, sb.st_size);
335 if (n != sb.st_size) {
336 perror("write");
337 fail_file();
338 }
339 if (file_append_size) {
340 n = write(fd_map, file_append, file_append_size);
341 if (n != file_append_size) {
342 perror("write");
343 fail_file();
344 }
345 }
346 close(fd_map);
347 if (rename(tmp_file, fname) < 0) {
348 perror(fname);
349 fail_file();
350 }
351 }
352
353 /* w8rev, w8nat, ...: Handle endianness. */
354
w8rev(uint64_t const x)355 static uint64_t w8rev(uint64_t const x)
356 {
357 return ((0xff & (x >> (0 * 8))) << (7 * 8))
358 | ((0xff & (x >> (1 * 8))) << (6 * 8))
359 | ((0xff & (x >> (2 * 8))) << (5 * 8))
360 | ((0xff & (x >> (3 * 8))) << (4 * 8))
361 | ((0xff & (x >> (4 * 8))) << (3 * 8))
362 | ((0xff & (x >> (5 * 8))) << (2 * 8))
363 | ((0xff & (x >> (6 * 8))) << (1 * 8))
364 | ((0xff & (x >> (7 * 8))) << (0 * 8));
365 }
366
w4rev(uint32_t const x)367 static uint32_t w4rev(uint32_t const x)
368 {
369 return ((0xff & (x >> (0 * 8))) << (3 * 8))
370 | ((0xff & (x >> (1 * 8))) << (2 * 8))
371 | ((0xff & (x >> (2 * 8))) << (1 * 8))
372 | ((0xff & (x >> (3 * 8))) << (0 * 8));
373 }
374
w2rev(uint16_t const x)375 static uint32_t w2rev(uint16_t const x)
376 {
377 return ((0xff & (x >> (0 * 8))) << (1 * 8))
378 | ((0xff & (x >> (1 * 8))) << (0 * 8));
379 }
380
w8nat(uint64_t const x)381 static uint64_t w8nat(uint64_t const x)
382 {
383 return x;
384 }
385
w4nat(uint32_t const x)386 static uint32_t w4nat(uint32_t const x)
387 {
388 return x;
389 }
390
w2nat(uint16_t const x)391 static uint32_t w2nat(uint16_t const x)
392 {
393 return x;
394 }
395
396 static uint64_t (*w8)(uint64_t);
397 static uint32_t (*w)(uint32_t);
398 static uint32_t (*w2)(uint16_t);
399
400 /* Names of the sections that could contain calls to mcount. */
401 static int
is_mcounted_section_name(char const * const txtname)402 is_mcounted_section_name(char const *const txtname)
403 {
404 return strcmp(".text", txtname) == 0 ||
405 strcmp(".init.text", txtname) == 0 ||
406 strcmp(".ref.text", txtname) == 0 ||
407 strcmp(".sched.text", txtname) == 0 ||
408 strcmp(".spinlock.text", txtname) == 0 ||
409 strcmp(".irqentry.text", txtname) == 0 ||
410 strcmp(".softirqentry.text", txtname) == 0 ||
411 strcmp(".kprobes.text", txtname) == 0 ||
412 strcmp(".cpuidle.text", txtname) == 0 ||
413 strcmp(".text.unlikely", txtname) == 0;
414 }
415
416 /* 32 bit and 64 bit are very similar */
417 #include "recordmcount.h"
418 #define RECORD_MCOUNT_64
419 #include "recordmcount.h"
420
arm_is_fake_mcount(Elf32_Rel const * rp)421 static int arm_is_fake_mcount(Elf32_Rel const *rp)
422 {
423 switch (ELF32_R_TYPE(w(rp->r_info))) {
424 case R_ARM_THM_CALL:
425 case R_ARM_CALL:
426 case R_ARM_PC24:
427 return 0;
428 }
429
430 return 1;
431 }
432
433 /* 64-bit EM_MIPS has weird ELF64_Rela.r_info.
434 * http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf
435 * We interpret Table 29 Relocation Operation (Elf64_Rel, Elf64_Rela) [p.40]
436 * to imply the order of the members; the spec does not say so.
437 * typedef unsigned char Elf64_Byte;
438 * fails on MIPS64 because their <elf.h> already has it!
439 */
440
441 typedef uint8_t myElf64_Byte; /* Type for a 8-bit quantity. */
442
443 union mips_r_info {
444 Elf64_Xword r_info;
445 struct {
446 Elf64_Word r_sym; /* Symbol index. */
447 myElf64_Byte r_ssym; /* Special symbol. */
448 myElf64_Byte r_type3; /* Third relocation. */
449 myElf64_Byte r_type2; /* Second relocation. */
450 myElf64_Byte r_type; /* First relocation. */
451 } r_mips;
452 };
453
MIPS64_r_sym(Elf64_Rel const * rp)454 static uint64_t MIPS64_r_sym(Elf64_Rel const *rp)
455 {
456 return w(((union mips_r_info){ .r_info = rp->r_info }).r_mips.r_sym);
457 }
458
MIPS64_r_info(Elf64_Rel * const rp,unsigned sym,unsigned type)459 static void MIPS64_r_info(Elf64_Rel *const rp, unsigned sym, unsigned type)
460 {
461 rp->r_info = ((union mips_r_info){
462 .r_mips = { .r_sym = w(sym), .r_type = type }
463 }).r_info;
464 }
465
466 static void
do_file(char const * const fname)467 do_file(char const *const fname)
468 {
469 Elf32_Ehdr *const ehdr = mmap_file(fname);
470 unsigned int reltype = 0;
471
472 w = w4nat;
473 w2 = w2nat;
474 w8 = w8nat;
475 switch (ehdr->e_ident[EI_DATA]) {
476 static unsigned int const endian = 1;
477 default:
478 fprintf(stderr, "unrecognized ELF data encoding %d: %s\n",
479 ehdr->e_ident[EI_DATA], fname);
480 fail_file();
481 break;
482 case ELFDATA2LSB:
483 if (*(unsigned char const *)&endian != 1) {
484 /* main() is big endian, file.o is little endian. */
485 w = w4rev;
486 w2 = w2rev;
487 w8 = w8rev;
488 }
489 ideal_nop4_arm = ideal_nop4_arm_le;
490 bl_mcount_arm = bl_mcount_arm_le;
491 push_arm = push_arm_le;
492 ideal_nop2_thumb = ideal_nop2_thumb_le;
493 push_bl_mcount_thumb = push_bl_mcount_thumb_le;
494 break;
495 case ELFDATA2MSB:
496 if (*(unsigned char const *)&endian != 0) {
497 /* main() is little endian, file.o is big endian. */
498 w = w4rev;
499 w2 = w2rev;
500 w8 = w8rev;
501 }
502 ideal_nop4_arm = ideal_nop4_arm_be;
503 bl_mcount_arm = bl_mcount_arm_be;
504 push_arm = push_arm_be;
505 ideal_nop2_thumb = ideal_nop2_thumb_be;
506 push_bl_mcount_thumb = push_bl_mcount_thumb_be;
507 break;
508 } /* end switch */
509 if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0
510 || w2(ehdr->e_type) != ET_REL
511 || ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
512 fprintf(stderr, "unrecognized ET_REL file %s\n", fname);
513 fail_file();
514 }
515
516 gpfx = 0;
517 switch (w2(ehdr->e_machine)) {
518 default:
519 fprintf(stderr, "unrecognized e_machine %u %s\n",
520 w2(ehdr->e_machine), fname);
521 fail_file();
522 break;
523 case EM_386:
524 reltype = R_386_32;
525 rel_type_nop = R_386_NONE;
526 make_nop = make_nop_x86;
527 ideal_nop = ideal_nop5_x86_32;
528 mcount_adjust_32 = -1;
529 break;
530 case EM_ARM: reltype = R_ARM_ABS32;
531 altmcount = "__gnu_mcount_nc";
532 make_nop = make_nop_arm;
533 rel_type_nop = R_ARM_NONE;
534 is_fake_mcount32 = arm_is_fake_mcount;
535 break;
536 case EM_AARCH64:
537 reltype = R_AARCH64_ABS64;
538 make_nop = make_nop_arm64;
539 rel_type_nop = R_AARCH64_NONE;
540 ideal_nop = ideal_nop4_arm64;
541 gpfx = '_';
542 break;
543 case EM_IA_64: reltype = R_IA64_IMM64; gpfx = '_'; break;
544 case EM_MIPS: /* reltype: e_class */ gpfx = '_'; break;
545 case EM_PPC: reltype = R_PPC_ADDR32; gpfx = '_'; break;
546 case EM_PPC64: reltype = R_PPC64_ADDR64; gpfx = '_'; break;
547 case EM_S390: /* reltype: e_class */ gpfx = '_'; break;
548 case EM_SH: reltype = R_SH_DIR32; break;
549 case EM_SPARCV9: reltype = R_SPARC_64; gpfx = '_'; break;
550 case EM_X86_64:
551 make_nop = make_nop_x86;
552 ideal_nop = ideal_nop5_x86_64;
553 reltype = R_X86_64_64;
554 rel_type_nop = R_X86_64_NONE;
555 mcount_adjust_64 = -1;
556 break;
557 } /* end switch */
558
559 switch (ehdr->e_ident[EI_CLASS]) {
560 default:
561 fprintf(stderr, "unrecognized ELF class %d %s\n",
562 ehdr->e_ident[EI_CLASS], fname);
563 fail_file();
564 break;
565 case ELFCLASS32:
566 if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr)
567 || w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) {
568 fprintf(stderr,
569 "unrecognized ET_REL file: %s\n", fname);
570 fail_file();
571 }
572 if (w2(ehdr->e_machine) == EM_MIPS) {
573 reltype = R_MIPS_32;
574 is_fake_mcount32 = MIPS32_is_fake_mcount;
575 }
576 do32(ehdr, fname, reltype);
577 break;
578 case ELFCLASS64: {
579 Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr;
580 if (w2(ghdr->e_ehsize) != sizeof(Elf64_Ehdr)
581 || w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) {
582 fprintf(stderr,
583 "unrecognized ET_REL file: %s\n", fname);
584 fail_file();
585 }
586 if (w2(ghdr->e_machine) == EM_S390) {
587 reltype = R_390_64;
588 mcount_adjust_64 = -14;
589 }
590 if (w2(ghdr->e_machine) == EM_MIPS) {
591 reltype = R_MIPS_64;
592 Elf64_r_sym = MIPS64_r_sym;
593 Elf64_r_info = MIPS64_r_info;
594 is_fake_mcount64 = MIPS64_is_fake_mcount;
595 }
596 do64(ghdr, fname, reltype);
597 break;
598 }
599 } /* end switch */
600
601 write_file(fname);
602 cleanup();
603 }
604
605 int
main(int argc,char * argv[])606 main(int argc, char *argv[])
607 {
608 const char ftrace[] = "/ftrace.o";
609 int ftrace_size = sizeof(ftrace) - 1;
610 int n_error = 0; /* gcc-4.3.0 false positive complaint */
611 int c;
612 int i;
613
614 while ((c = getopt(argc, argv, "w")) >= 0) {
615 switch (c) {
616 case 'w':
617 warn_on_notrace_sect = 1;
618 break;
619 default:
620 fprintf(stderr, "usage: recordmcount [-w] file.o...\n");
621 return 0;
622 }
623 }
624
625 if ((argc - optind) < 1) {
626 fprintf(stderr, "usage: recordmcount [-w] file.o...\n");
627 return 0;
628 }
629
630 /* Process each file in turn, allowing deep failure. */
631 for (i = optind; i < argc; i++) {
632 char *file = argv[i];
633 int const sjval = setjmp(jmpenv);
634 int len;
635
636 /*
637 * The file kernel/trace/ftrace.o references the mcount
638 * function but does not call it. Since ftrace.o should
639 * not be traced anyway, we just skip it.
640 */
641 len = strlen(file);
642 if (len >= ftrace_size &&
643 strcmp(file + (len - ftrace_size), ftrace) == 0)
644 continue;
645
646 switch (sjval) {
647 default:
648 fprintf(stderr, "internal error: %s\n", file);
649 exit(1);
650 break;
651 case SJ_SETJMP: /* normal sequence */
652 /* Avoid problems if early cleanup() */
653 fd_map = -1;
654 mmap_failed = 1;
655 file_map = NULL;
656 file_ptr = NULL;
657 file_updated = 0;
658 do_file(file);
659 break;
660 case SJ_FAIL: /* error in do_file or below */
661 fprintf(stderr, "%s: failed\n", file);
662 ++n_error;
663 break;
664 case SJ_SUCCEED: /* premature success */
665 /* do nothing */
666 break;
667 } /* end switch */
668 }
669 return !!n_error;
670 }
671