3
* Apply a "universal" diff.
4
* Adapted from toybox's patch implementation.
6
* Copyright 2007 Rob Landley <rob@landley.net>
8
* see http://www.opengroup.org/onlinepubs/009695399/utilities/patch.html
9
* (But only does -u, because who still cares about "ed"?)
13
* -l treat all whitespace as a single space
15
* -D define wrap #ifdef and #ifndef around changes
16
* -o outfile output here instead of in place
17
* -r rejectfile write rejected hunks to this file
19
* -f force (no questions asked)
20
* -F fuzz (number, default 2)
21
* [file] which file to patch
24
//config: bool "patch (9.4 kb)"
27
//config: Apply a unified diff formatted patch.
29
//applet:IF_PATCH(APPLET(patch, BB_DIR_USR_BIN, BB_SUID_DROP))
31
//kbuild:lib-$(CONFIG_PATCH) += patch.o
33
//usage:#define patch_trivial_usage
34
//usage: "[OPTIONS] [ORIGFILE [PATCHFILE]]"
35
//usage:#define patch_full_usage "\n\n"
36
//usage: " -p N Strip N leading components from file names"
37
//usage: "\n -i DIFF Read DIFF instead of stdin"
38
//usage: "\n -R Reverse patch"
39
//usage: "\n -N Ignore already applied patches"
40
//usage: "\n -E Remove output files if they become empty"
41
//usage: IF_LONG_OPTS(
42
//usage: "\n --dry-run Don't actually change files"
44
/* -u "interpret as unified diff" is supported but not documented: this info is not useful for --help */
46
//usage:#define patch_example_usage
47
//usage: "$ patch -p1 < example.diff\n"
48
//usage: "$ patch -p0 -i example.diff"
57
struct double_list *next;
58
struct double_list *prev;
62
// Free all the elements of a linked list
63
// Call freeit() on each element before freeing it.
64
static void dlist_free(struct double_list *list, void (*freeit)(void *data))
70
// Bail out also if list is circular.
71
if (list == pop) break;
75
// Add an entry before "list" element in (circular) doubly linked list
76
static struct double_list *dlist_add(struct double_list **list, char *data)
78
struct double_list *llist;
79
struct double_list *line = xmalloc(sizeof(*line));
84
struct double_list *p;
86
p = line->prev = llist->prev;
87
// (list is circular, we assume p is never NULL)
91
*list = line->next = line->prev = line;
101
struct double_list *current_hunk;
103
long oldline, oldlen, newline, newlen;
105
int context, state, hunknum;
111
#define TT (*ptr_to_globals)
112
#define INIT_TT() do { \
113
SET_PTR_TO_GLOBALS(xzalloc(sizeof(TT))); \
117
#define FLAG_STR "Rup:i:NEfg"
118
/* FLAG_REVERSE must be == 1! Code uses this fact. */
119
#define FLAG_REVERSE (1 << 0)
120
#define FLAG_u (1 << 1)
121
#define FLAG_PATHLEN (1 << 2)
122
#define FLAG_INPUT (1 << 3)
123
#define FLAG_IGNORE (1 << 4)
124
#define FLAG_RMEMPTY (1 << 5)
125
#define FLAG_f_unused (1 << 6)
126
#define FLAG_g_unused (1 << 7)
127
#define FLAG_dry_run ((1 << 8) * ENABLE_LONG_OPTS)
130
// Dispose of a line of input, either by writing it out or discarding it.
132
// state < 2: just free
133
// state = 2: write whole line to stderr
134
// state = 3: write whole line to fileout
135
// state > 3: write line+1 to fileout when *line != state
137
static void do_line(void *data)
139
struct double_list *dlist = data;
141
if (TT.state>1 && *dlist->data != TT.state)
142
fdprintf(TT.state == 2 ? 2 : TT.fileout,
143
"%s\n", dlist->data+(TT.state>3 ? 1 : 0));
145
if (PATCH_DEBUG) fdprintf(2, "DO %d: %s\n", TT.state, dlist->data);
151
static void finish_oldfile(void)
154
// Copy the rest of the data and replace the original with the copy.
157
if (TT.filein != -1) {
158
bb_copyfd_eof(TT.filein, TT.fileout);
163
if (!ENABLE_LONG_OPTS || TT.tempname[0]) { /* not --dry-run? */
164
temp = xstrdup(TT.tempname);
165
temp[strlen(temp) - 6] = '\0';
166
rename(TT.tempname, temp);
173
TT.fileout = TT.filein = -1;
176
static void fail_hunk(void)
178
if (!TT.current_hunk) return;
180
fdprintf(2, "Hunk %d FAILED %ld/%ld.\n", TT.hunknum, TT.oldline, TT.newline);
183
// If we got to this point, we've seeked to the end. Discard changes to
184
// this file and advance to next file.
187
TT.current_hunk->prev->next = NULL;
188
dlist_free(TT.current_hunk, do_line);
189
TT.current_hunk = NULL;
191
// Abort the copy and delete the temporary file.
194
if (!ENABLE_LONG_OPTS || TT.tempname[0]) { /* not --dry-run? */
203
// Given a hunk of a unified diff, make the appropriate change to the file.
204
// This does not use the location information, but instead treats a hunk
205
// as a sort of regex. Copies data from input to output until it finds
206
// the change to be made, then outputs the changed data and returns.
207
// (Finding EOF first is an error.) This is a single pass operation, so
208
// multiple hunks must occur in order in the file.
210
static int apply_one_hunk(void)
212
struct double_list *plist, *buf = NULL, *check;
213
int matcheof = 0, reverse = option_mask32 & FLAG_REVERSE, backwarn = 0;
214
/* Do we try "dummy" revert to check whether
215
* to silently skip this hunk? Used to implement -N.
217
int dummy_revert = 0;
219
// Break doubly linked list so we can use singly linked traversal function.
220
TT.current_hunk->prev->next = NULL;
222
// Match EOF if there aren't as many ending context lines as beginning
223
for (plist = TT.current_hunk; plist; plist = plist->next) {
224
if (plist->data[0]==' ') matcheof++;
226
if (PATCH_DEBUG) fdprintf(2, "HUNK:%s\n", plist->data);
228
matcheof = !matcheof || matcheof < TT.context;
230
if (PATCH_DEBUG) fdprintf(2,"MATCHEOF=%c\n", matcheof ? 'Y' : 'N');
232
// Loop through input data searching for this hunk. Match all context
233
// lines and all lines to be removed until we've found the end of a
235
plist = TT.current_hunk;
237
if (reverse ? TT.oldlen : TT.newlen) for (;;) {
238
//FIXME: this performs 1-byte reads:
239
char *data = xmalloc_reads(TT.filein, NULL);
243
// Figure out which line of hunk to compare with next. (Skip lines
244
// of the hunk we'd be adding.)
245
while (plist && *plist->data == "+-"[reverse]) {
246
if (data && strcmp(data, plist->data+1) == 0) {
248
backwarn = TT.linenum;
249
if (option_mask32 & FLAG_IGNORE) {
261
if (PATCH_DEBUG) fdprintf(2, "INEOF\n");
263
// Does this hunk need to match EOF?
264
if (!plist && matcheof) break;
267
fdprintf(2,"Possibly reversed hunk %d at %ld\n",
268
TT.hunknum, TT.linenum);
270
// File ended before we found a place for this hunk.
275
if (PATCH_DEBUG) fdprintf(2, "IN: %s\n", data);
276
check = dlist_add(&buf, data);
278
// Compare this line with next expected line of hunk.
279
// todo: teach the strcmp() to ignore whitespace.
281
// A match can fail because the next line doesn't match, or because
282
// we hit the end of a hunk that needed EOF, and this isn't EOF.
284
// If match failed, flush first line of buffered data and
285
// recheck buffered data for a new match until we find one or run
289
while (plist && *plist->data == "+-"[reverse]) {
290
if (strcmp(check->data, plist->data+1) == 0
293
backwarn = TT.linenum;
294
if (option_mask32 & FLAG_IGNORE) {
301
if (!plist || strcmp(check->data, plist->data+1)) {
302
// Match failed. Write out first line of buffered data and
303
// recheck remaining buffered data for a new match.
306
fdprintf(2, "NOT: %s\n", plist ? plist->data : "EOF");
311
check->prev->next = buf;
312
buf->prev = check->prev;
314
plist = TT.current_hunk;
316
// If we've reached the end of the buffer without confirming a
317
// match, read more lines.
325
fdprintf(2, "MAYBE: %s\n", plist->data);
326
// This line matches. Advance plist, detect successful match.
328
if (!plist && !matcheof) goto out;
330
if (check == buf) break;
335
// We have a match. Emit changed data.
336
TT.state = "-+"[reverse ^ dummy_revert];
337
dlist_free(TT.current_hunk, do_line);
338
TT.current_hunk = NULL;
342
buf->prev->next = NULL;
343
dlist_free(buf, do_line);
349
// Read a patch file and find hunks, opening/creating/deleting files.
350
// Call apply_one_hunk() on each hunk.
352
// state 0: Not in a hunk, look for +++.
353
// state 1: Found +++ file indicator, look for @@
354
// state 2: In hunk: counting initial context lines
355
// state 3: In hunk: getting body
356
// Like GNU patch, we don't require a --- line before the +++, and
357
// also allow the --- after the +++ line.
359
int patch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
360
int patch_main(int argc UNUSED_PARAM, char **argv)
363
int reverse, state = 0;
364
char *oldname = NULL, *newname = NULL;
366
long oldlen = oldlen; /* for compiler */
367
long newlen = newlen; /* for compiler */
370
static const char patch_longopts[] ALIGN1 =
371
"reverse\0" No_argument "R"
372
"unified\0" No_argument "u"
373
"strip\0" Required_argument "p"
374
"input\0" Required_argument "i"
375
"forward\0" No_argument "N"
377
"remove-empty-files\0" No_argument "E" /*ignored*/
378
/* "debug" Required_argument "x" */
380
/* "Assume user knows what [s]he is doing, do not ask any questions": */
381
"force\0" No_argument "f" /*ignored*/
383
/* "Controls actions when a file is under RCS or SCCS control,
384
* and does not exist or is read-only and matches the default version,
385
* or when a file is under ClearCase control and does not exist..."
386
* IOW: rather obscure option.
387
* But Gentoo's portage does use -g0
389
"get\0" Required_argument "g" /*ignored*/
391
"dry-run\0" No_argument "\xfd"
393
"backup-if-mismatch\0" No_argument "\xfe" /*ignored*/
394
"no-backup-if-mismatch\0" No_argument "\xff" /*ignored*/
402
opts = getopt32long(argv, FLAG_STR, patch_longopts, &opt_p, &opt_i);
404
opts = getopt32(argv, FLAG_STR, &opt_p, &opt_i);
406
//bb_error_msg_and_die("opts:%x", opts);
409
reverse = opts & FLAG_REVERSE;
410
TT.prefix = (opts & FLAG_PATHLEN) ? xatoi(opt_p) : 0; // can be negative!
411
TT.filein = TT.fileout = -1;
412
if (opts & FLAG_INPUT) {
413
xmove_fd(xopen_stdin(opt_i), STDIN_FILENO);
415
if (argv[0] && argv[1]) {
416
xmove_fd(xopen_stdin(argv[1]), STDIN_FILENO);
420
// Loop through the lines in the patch
424
patchline = xmalloc_fgetline(stdin);
425
if (!patchline) break;
427
// Other versions of patch accept damaged patches,
428
// so we need to also.
431
patchline = xstrdup(" ");
434
// Are we assembling a hunk?
436
if (*patchline==' ' || *patchline=='+' || *patchline=='-') {
437
dlist_add(&TT.current_hunk, patchline);
439
if (*patchline != '+') oldlen--;
440
if (*patchline != '-') newlen--;
443
if (*patchline==' ' && state==2) TT.context++;
446
// If we've consumed all expected hunk lines, apply the hunk.
448
if (!oldlen && !newlen) state = apply_one_hunk();
457
if (is_prefixed_with(patchline, "--- ") || is_prefixed_with(patchline, "+++ ")) {
458
char *s, **name = reverse ? &newname : &oldname;
461
if (*patchline == '+') {
462
name = reverse ? &oldname : &newname;
470
// Trim date from end of filename (if any). We don't care.
471
for (s = patchline+4; *s && *s!='\t'; s++)
472
if (*s=='\\' && s[1]) s++;
474
if (i>1900 && i<=1970)
475
*name = xstrdup("/dev/null");
478
*name = xstrdup(patchline+4);
482
// We defer actually opening the file because svn produces broken
483
// patches that don't signal they want to create a new file the
484
// way the patch man page says, so you have to read the first hunk
487
// Start a new hunk? Usually @@ -oldline,oldlen +newline,newlen @@
488
// but a missing ,value means the value is 1.
489
} else if (state == 1 && is_prefixed_with(patchline, "@@ -")) {
491
char *s = patchline+4;
493
// Read oldline[,oldlen] +newline[,newlen]
495
TT.oldlen = oldlen = TT.newlen = newlen = 1;
496
TT.oldline = strtol(s, &s, 10);
497
if (*s == ',') TT.oldlen = oldlen = strtol(s+1, &s, 10);
498
TT.newline = strtol(s+2, &s, 10);
499
if (*s == ',') TT.newlen = newlen = strtol(s+1, &s, 10);
501
if (oldlen < 1 && newlen < 1)
502
bb_error_msg_and_die("Really? %s", patchline);
507
// If the --- line is missing or malformed, either oldname
508
// or (for -R) newname could be NULL -- but not both. Like
509
// GNU patch, proceed based on the +++ line, and avoid SEGVs.
511
oldname = xstrdup("MISSING_FILENAME");
513
newname = xstrdup("MISSING_FILENAME");
515
// If this is the first hunk, open the file.
516
if (TT.filein == -1) {
517
int oldsum, newsum, empty = 0;
520
oldsum = TT.oldline + oldlen;
521
newsum = TT.newline + newlen;
523
name = reverse ? oldname : newname;
525
// We're deleting oldname if new file is /dev/null (before -p)
526
// or if new hunk is empty (zero context) after patching
527
if (strcmp(name, "/dev/null") == 0 || !(reverse ? oldsum : newsum)) {
528
name = reverse ? newname : oldname;
532
// Handle -p path truncation.
533
for (i = 0, s = name; *s;) {
534
if ((option_mask32 & FLAG_PATHLEN) && TT.prefix == i)
543
// If "patch FILE_TO_PATCH", completely ignore name from patch
548
// File is empty after the patches have been applied
550
if (option_mask32 & FLAG_RMEMPTY) {
551
// If flag -E or --remove-empty-files is set
552
printf("removing %s\n", name);
553
if (!(opts & FLAG_dry_run))
556
printf("patching file %s\n", name);
557
if (!(opts & FLAG_dry_run))
558
xclose(xopen(name, O_WRONLY | O_TRUNC));
560
// If we've got a file to open, do so.
561
} else if (!(option_mask32 & FLAG_PATHLEN) || i <= TT.prefix) {
564
// If the old file was null, we're creating a new one.
565
if (strcmp(oldname, "/dev/null") == 0 || !oldsum) {
566
printf("creating %s\n", name);
567
if (!(opts & FLAG_dry_run)) {
568
s = strrchr(name, '/');
571
bb_make_directory(name, -1, FILEUTILS_RECUR);
574
TT.filein = xopen(name, O_CREAT|O_EXCL|O_RDWR);
576
TT.filein = xopen("/dev/null", O_RDONLY);
579
printf("patching file %s\n", name);
580
TT.filein = xopen(name, O_RDONLY);
583
if (!(opts & FLAG_dry_run)) {
584
TT.tempname = xasprintf("%sXXXXXX", name);
585
TT.fileout = xmkstemp(TT.tempname);
586
// Set permissions of output file
587
fstat(TT.filein, &statbuf);
588
fchmod(TT.fileout, statbuf.st_mode);
590
TT.tempname = (char*)"";
591
TT.fileout = xopen("/dev/null", O_WRONLY);
603
// If we didn't continue above, discard this line.
609
if (ENABLE_FEATURE_CLEAN_UP) {