busybox/editors/patch.c

/* Adapted from toybox's patch. */

/* vi: set sw=4 ts=4:
 *
 * patch.c - Apply a "universal" diff.
 *
 * Copyright 2007 Rob Landley <rob@landley.net>
 *
 * see http://www.opengroup.org/onlinepubs/009695399/utilities/patch.html
 * (But only does -u, because who still cares about "ed"?)
 *
 * TODO:
 * -b backup
 * -l treat all whitespace as a single space
 * -d chdir first
 * -D define wrap #ifdef and #ifndef around changes
 * -o outfile output here instead of in place
 * -r rejectfile write rejected hunks to this file
 *
 * -E remove empty files --remove-empty-files
 * -f force (no questions asked)
 * -F fuzz (number, default 2)
 * [file] which file to patch

USE_PATCH(NEWTOY(patch, USE_TOYBOX_DEBUG("x")"up#i:R", TOYFLAG_USR|TOYFLAG_BIN))

config PATCH
	bool "patch"
	default y
	help
	  usage: patch [-i file] [-p depth] [-Ru]

	  Apply a unified diff to one or more files.

	  -i	Input file (defaults=stdin)
	  -p	number of '/' to strip from start of file paths (default=all)
	  -R	Reverse patch.
	  -u	Ignored (only handles "unified" diffs)

	  This version of patch only handles unified diffs, and only modifies
	  a file when all all hunks to that file apply.  Patch prints failed
	  hunks to stderr, and exits with nonzero status if any hunks fail.

	  A file compared against /dev/null (or with a date <= the epoch) is
	  created/deleted as appropriate.
*/
#include "libbb.h"

struct double_list {
	struct double_list *next;
	struct double_list *prev;
	char *data;
};

// Return the first item from the list, advancing the list (which must be called
// as &list)
static
void *TOY_llist_pop(void *list)
{
	// I'd use a void ** for the argument, and even accept the typecast in all
	// callers as documentation you need the &, except the stupid compiler
	// would then scream about type-punned pointers.  Screw it.
	void **llist = (void **)list;
	void **next = (void **)*llist;
	*llist = *next;

	return (void *)next;
}

// Free all the elements of a linked list
// if freeit!=NULL call freeit() on each element before freeing it.
static
void TOY_llist_free(void *list, void (*freeit)(void *data))
{
	while (list) {
		void *pop = TOY_llist_pop(&list);
		if (freeit) freeit(pop);
		else free(pop);

		// End doubly linked list too.
		if (list==pop) break;
	}
}
//Override bbox's names
#define llist_pop TOY_llist_pop
#define llist_free TOY_llist_free

// Add an entry to the end off a doubly linked list
static
struct double_list *dlist_add(struct double_list **list, char *data)
{
	struct double_list *line = xmalloc(sizeof(struct double_list));

	line->data = data;
	if (*list) {
		line->next = *list;
		line->prev = (*list)->prev;
		(*list)->prev->next = line;
		(*list)->prev = line;
	} else *list = line->next = line->prev = line;

	return line;
}

// Ensure entire path exists.
// If mode != -1 set permissions on newly created dirs.
// Requires that path string be writable (for temporary null terminators).
static
void xmkpath(char *path, int mode)
{
	char *p, old;
	mode_t mask;
	int rc;
	struct stat st;

	for (p = path; ; p++) {
		if (!*p || *p == '/') {
			old = *p;
			*p = rc = 0;
			if (stat(path, &st) || !S_ISDIR(st.st_mode)) {
				if (mode != -1) {
					mask = umask(0);
					rc = mkdir(path, mode);
					umask(mask);
				} else rc = mkdir(path, 0777);
			}
			*p = old;
			if(rc) bb_perror_msg_and_die("mkpath '%s'", path);
		}
		if (!*p) break;
	}
}

// Slow, but small.
static
char *get_rawline(int fd, long *plen, char end)
{
	char c, *buf = NULL;
	long len = 0;

	for (;;) {
		if (1>read(fd, &c, 1)) break;
		if (!(len & 63)) buf=xrealloc(buf, len+65);
		if ((buf[len++]=c) == end) break;
	}
	if (buf) buf[len]=0;
	if (plen) *plen = len;

	return buf;
}

static
char *get_line(int fd)
{
	long len;
	char *buf = get_rawline(fd, &len, '\n');

	if (buf && buf[--len]=='\n') buf[len]=0;

	return buf;
}

// Copy the rest of in to out and close both files.
static
void xsendfile(int in, int out)
{
	long len;
	char buf[4096];

	if (in<0) return;
	for (;;) {
		len = safe_read(in, buf, 4096);
		if (len<1) break;
		xwrite(out, buf, len);
	}
}

// Copy the rest of the data and replace the original with the copy.
static
void replace_tempfile(int fdin, int fdout, char **tempname)
{
	char *temp = xstrdup(*tempname);

	temp[strlen(temp)-6]=0;
	if (fdin != -1) {
		xsendfile(fdin, fdout);
		xclose(fdin);
	}
	xclose(fdout);
	rename(*tempname, temp);
	free(*tempname);
	free(temp);
	*tempname = NULL;
}

// Open a temporary file to copy an existing file into.
static
int copy_tempfile(int fdin, char *name, char **tempname)
{
	struct stat statbuf;
	int fd;

	*tempname = xasprintf("%sXXXXXX", name);
	fd = mkstemp(*tempname);
	if(-1 == fd) bb_perror_msg_and_die("no temp file");

	// Set permissions of output file
	fstat(fdin, &statbuf);
	fchmod(fd, statbuf.st_mode);

	return fd;
}

// Abort the copy and delete the temporary file.
static
void delete_tempfile(int fdin, int fdout, char **tempname)
{
	close(fdin);
	close(fdout);
	unlink(*tempname);
	free(*tempname);
	*tempname = NULL;
}


struct globals {
	char *infile;
	long prefix;

	struct double_list *current_hunk;
	long oldline, oldlen, newline, newlen;
	long linenum;
	int context, state, filein, fileout, filepatch, hunknum;
	char *tempname;

	// was toys.foo:
	int exitval;
};
#define TT (*ptr_to_globals)
#define INIT_TT() do { \
	SET_PTR_TO_GLOBALS(xzalloc(sizeof(TT))); \
} while (0)


#define FLAG_STR "Rup:i:Nx"
/* FLAG_REVERSE must be == 1! Code uses this fact. */
#define FLAG_REVERSE (1 << 0)
#define FLAG_u       (1 << 1)
#define FLAG_PATHLEN (1 << 2)
#define FLAG_INPUT   (1 << 3)
#define FLAG_IGNORE  (1 << 4)
//non-standard:
#define FLAG_DEBUG   (1 << 5)

// Dispose of a line of input, either by writing it out or discarding it.

// state < 2: just free
// state = 2: write whole line to stderr
// state = 3: write whole line to fileout
// state > 3: write line+1 to fileout when *line != state

#define PATCH_DEBUG (option_mask32 & FLAG_DEBUG)

static void do_line(void *data)
{
	struct double_list *dlist = (struct double_list *)data;

	if (TT.state>1 && *dlist->data != TT.state)
		fdprintf(TT.state == 2 ? 2 : TT.fileout,
			"%s\n", dlist->data+(TT.state>3 ? 1 : 0));

	if (PATCH_DEBUG) fdprintf(2, "DO %d: %s\n", TT.state, dlist->data);

	free(dlist->data);
	free(data);
}

static void finish_oldfile(void)
{
	if (TT.tempname) replace_tempfile(TT.filein, TT.fileout, &TT.tempname);
	TT.fileout = TT.filein = -1;
}

static void fail_hunk(void)
{
	if (!TT.current_hunk) return;
	TT.current_hunk->prev->next = 0;

	fdprintf(2, "Hunk %d FAILED %ld/%ld.\n", TT.hunknum, TT.oldline, TT.newline);
	TT.exitval = 1;

	// If we got to this point, we've seeked to the end.  Discard changes to
	// this file and advance to next file.

	TT.state = 2;
	llist_free(TT.current_hunk, do_line);
	TT.current_hunk = NULL;
	delete_tempfile(TT.filein, TT.fileout, &TT.tempname);
	TT.state = 0;
}

// Given a hunk of a unified diff, make the appropriate change to the file.
// This does not use the location information, but instead treats a hunk
// as a sort of regex.  Copies data from input to output until it finds
// the change to be made, then outputs the changed data and returns.
// (Finding EOF first is an error.)  This is a single pass operation, so
// multiple hunks must occur in order in the file.

static int apply_one_hunk(void)
{
	struct double_list *plist, *buf = NULL, *check;
	int matcheof = 0, reverse = option_mask32 & FLAG_REVERSE, backwarn = 0;
	/* Do we try "dummy" revert to check whether
	 * to silently skip this hunk? Used to implement -N.
	 */
	int dummy_revert = 0;

	// Break doubly linked list so we can use singly linked traversal function.
	TT.current_hunk->prev->next = NULL;

	// Match EOF if there aren't as many ending context lines as beginning
	for (plist = TT.current_hunk; plist; plist = plist->next) {
		if (plist->data[0]==' ') matcheof++;
		else matcheof = 0;
		if (PATCH_DEBUG) fdprintf(2, "HUNK:%s\n", plist->data);
	}
	matcheof = matcheof < TT.context;

	if (PATCH_DEBUG) fdprintf(2,"MATCHEOF=%c\n", matcheof ? 'Y' : 'N');

	// Loop through input data searching for this hunk.  Match all context
	// lines and all lines to be removed until we've found the end of a
	// complete hunk.
	plist = TT.current_hunk;
	buf = NULL;
	if (TT.context) for (;;) {
		char *data = get_line(TT.filein);

		TT.linenum++;

		// Figure out which line of hunk to compare with next.  (Skip lines
		// of the hunk we'd be adding.)
		while (plist && *plist->data == "+-"[reverse]) {
			if (data && !strcmp(data, plist->data+1)) {
				if (!backwarn) {
					backwarn++;
					if (option_mask32 & FLAG_IGNORE) {
						dummy_revert = 1;
						reverse ^= 1;
						continue;
					}
					fdprintf(2,"Possibly reversed hunk %d at %ld\n",
						TT.hunknum, TT.linenum);
				}
			}
			plist = plist->next;
		}

		// Is this EOF?
		if (!data) {
			if (PATCH_DEBUG) fdprintf(2, "INEOF\n");

			// Does this hunk need to match EOF?
			if (!plist && matcheof) break;

			// File ended before we found a place for this hunk.
			fail_hunk();
			goto done;
		} else if (PATCH_DEBUG) fdprintf(2, "IN: %s\n", data);
		check = dlist_add(&buf, data);

		// Compare this line with next expected line of hunk.
		// todo: teach the strcmp() to ignore whitespace.

		// A match can fail because the next line doesn't match, or because
		// we hit the end of a hunk that needed EOF, and this isn't EOF.

		// If match failed, flush first line of buffered data and
		// recheck buffered data for a new match until we find one or run
		// out of buffer.

		for (;;) {
			if (!plist || strcmp(check->data, plist->data+1)) {
				// Match failed.  Write out first line of buffered data and
				// recheck remaining buffered data for a new match.

				if (PATCH_DEBUG)
					fdprintf(2, "NOT: %s\n", plist->data);

				TT.state = 3;
				check = llist_pop(&buf);
				check->prev->next = buf;
				buf->prev = check->prev;
				do_line(check);
				plist = TT.current_hunk;

				// If we've reached the end of the buffer without confirming a
				// match, read more lines.
				if (check==buf) {
					buf = 0;
					break;
				}
				check = buf;
			} else {
				if (PATCH_DEBUG)
					fdprintf(2, "MAYBE: %s\n", plist->data);
				// This line matches.  Advance plist, detect successful match.
				plist = plist->next;
				if (!plist && !matcheof) goto out;
				check = check->next;
				if (check == buf) break;
			}
		}
	}
out:
	// We have a match.  Emit changed data.
	TT.state = "-+"[reverse ^ dummy_revert];
	llist_free(TT.current_hunk, do_line);
	TT.current_hunk = NULL;
	TT.state = 1;
done:
	if (buf) {
		buf->prev->next = NULL;
		llist_free(buf, do_line);
	}

	return TT.state;
}

// Read a patch file and find hunks, opening/creating/deleting files.
// Call apply_one_hunk() on each hunk.

// state 0: Not in a hunk, look for +++.
// state 1: Found +++ file indicator, look for @@
// state 2: In hunk: counting initial context lines
// state 3: In hunk: getting body

int patch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int patch_main(int argc UNUSED_PARAM, char **argv)
{
	int opts;
	int reverse, state = 0;
	char *oldname = NULL, *newname = NULL;
	char *opt_p, *opt_i;

	INIT_TT();

	opts = getopt32(argv, FLAG_STR, &opt_p, &opt_i);
	argv += optind;
	reverse = opts & FLAG_REVERSE;
	TT.prefix = (opts & FLAG_PATHLEN) ? xatoi(opt_p) : 0; // can be negative!
	TT.filein = TT.fileout = -1;
	if (opts & FLAG_INPUT) {
		TT.filepatch = xopen_stdin(opt_i);
	} else {
		if (argv[0] && argv[1]) {
			TT.filepatch = xopen_stdin(argv[1]);
		}
	}
	if (argv[0]) {
		oldname = xstrdup(argv[0]);
		newname = xstrdup(argv[0]);
	}

	// Loop through the lines in the patch
	for(;;) {
		char *patchline;

		patchline = get_line(TT.filepatch);
		if (!patchline) break;

		// Other versions of patch accept damaged patches,
		// so we need to also.
		if (!*patchline) {
			free(patchline);
			patchline = xstrdup(" ");
		}

		// Are we assembling a hunk?
		if (state >= 2) {
			if (*patchline==' ' || *patchline=='+' || *patchline=='-') {
				dlist_add(&TT.current_hunk, patchline);

				if (*patchline != '+') TT.oldlen--;
				if (*patchline != '-') TT.newlen--;

				// Context line?
				if (*patchline==' ' && state==2) TT.context++;
				else state=3;

				// If we've consumed all expected hunk lines, apply the hunk.

				if (!TT.oldlen && !TT.newlen) state = apply_one_hunk();
				continue;
			}
			fail_hunk();
			state = 0;
			continue;
		}

		// Open a new file?
		if (!strncmp("--- ", patchline, 4) || !strncmp("+++ ", patchline, 4)) {
			char *s, **name = reverse ? &newname : &oldname;
			int i;

			if (*patchline == '+') {
				name = reverse ? &oldname : &newname;
				state = 1;
			}

			finish_oldfile();

			if (!argv[0]) {
				free(*name);
				// Trim date from end of filename (if any).  We don't care.
				for (s = patchline+4; *s && *s!='\t'; s++)
					if (*s=='\\' && s[1]) s++;
				i = atoi(s);
				if (i>1900 && i<=1970)
					*name = xstrdup("/dev/null");
				else {
					*s = 0;
					*name = xstrdup(patchline+4);
				}
			}

			// We defer actually opening the file because svn produces broken
			// patches that don't signal they want to create a new file the
			// way the patch man page says, so you have to read the first hunk
			// and _guess_.

		// Start a new hunk?  Usually @@ -oldline,oldlen +newline,newlen @@
		// but a missing ,value means the value is 1.
		} else if (state == 1 && !strncmp("@@ -", patchline, 4)) {
			int i;
			char *s = patchline+4;

			// Read oldline[,oldlen] +newline[,newlen]

			TT.oldlen = TT.newlen = 1;
			TT.oldline = strtol(s, &s, 10);
			if (*s == ',') TT.oldlen=strtol(s+1, &s, 10);
			TT.newline = strtol(s+2, &s, 10);
			if (*s == ',') TT.newlen = strtol(s+1, &s, 10);

			TT.context = 0;
			state = 2;

			// If this is the first hunk, open the file.
			if (TT.filein == -1) {
				int oldsum, newsum, del = 0;
				char *name;

 				oldsum = TT.oldline + TT.oldlen;
				newsum = TT.newline + TT.newlen;

				name = reverse ? oldname : newname;

				// We're deleting oldname if new file is /dev/null (before -p)
				// or if new hunk is empty (zero context) after patching
				if (!strcmp(name, "/dev/null") || !(reverse ? oldsum : newsum))
				{
					name = reverse ? newname : oldname;
					del++;
				}

				// handle -p path truncation.
				for (i=0, s = name; *s;) {
					if ((option_mask32 & FLAG_PATHLEN) && TT.prefix == i) break;
					if (*(s++)=='/') {
						name = s;
						i++;
					}
				}

				if (del) {
					printf("removing %s\n", name);
					xunlink(name);
					state = 0;
				// If we've got a file to open, do so.
				} else if (!(option_mask32 & FLAG_PATHLEN) || i <= TT.prefix) {
					// If the old file was null, we're creating a new one.
					if (!strcmp(oldname, "/dev/null") || !oldsum) {
						printf("creating %s\n", name);
						s = strrchr(name, '/');
						if (s) {
							*s = 0;
							xmkpath(name, -1);
							*s = '/';
						}
						TT.filein = xopen3(name, O_CREAT|O_EXCL|O_RDWR, 0666);
					} else {
						printf("patching file %s\n", name);
						TT.filein = xopen(name, O_RDWR);
					}
					TT.fileout = copy_tempfile(TT.filein, name, &TT.tempname);
					TT.linenum = 0;
					TT.hunknum = 0;
				}
			}

			TT.hunknum++;

			continue;
		}

		// If we didn't continue above, discard this line.
		free(patchline);
	}

	finish_oldfile();

	if (ENABLE_FEATURE_CLEAN_UP) {
		close(TT.filepatch);
		free(oldname);
		free(newname);
	}

	return TT.exitval;
}
1	niro	1179	/* Adapted from toybox's patch. */
2
3			/* vi: set sw=4 ts=4:
4	niro	532	*
5	niro	1179	* patch.c - Apply a "universal" diff.
6	niro	532	*
7	niro	1179	* Copyright 2007 Rob Landley <rob@landley.net>
8	niro	532	*
9	niro	1179	* see http://www.opengroup.org/onlinepubs/009695399/utilities/patch.html
10			* (But only does -u, because who still cares about "ed"?)
11	niro	532	*
12	niro	1179	* TODO:
13			* -b backup
14			* -l treat all whitespace as a single space
15			* -d chdir first
16			* -D define wrap #ifdef and #ifndef around changes
17			* -o outfile output here instead of in place
18			* -r rejectfile write rejected hunks to this file
19			*
20			* -E remove empty files --remove-empty-files
21			* -f force (no questions asked)
22			* -F fuzz (number, default 2)
23			* [file] which file to patch
24	niro	532
25	niro	1179	USE_PATCH(NEWTOY(patch, USE_TOYBOX_DEBUG("x")"up#i:R", TOYFLAG_USR\|TOYFLAG_BIN))
26
27			config PATCH
28			bool "patch"
29			default y
30			help
31			usage: patch [-i file] [-p depth] [-Ru]
32
33			Apply a unified diff to one or more files.
34
35			-i Input file (defaults=stdin)
36			-p number of '/' to strip from start of file paths (default=all)
37			-R Reverse patch.
38			-u Ignored (only handles "unified" diffs)
39
40			This version of patch only handles unified diffs, and only modifies
41			a file when all all hunks to that file apply. Patch prints failed
42			hunks to stderr, and exits with nonzero status if any hunks fail.
43
44			A file compared against /dev/null (or with a date <= the epoch) is
45			created/deleted as appropriate.
46			*/
47	niro	816	#include "libbb.h"
48	niro	532
49	niro	1179	struct double_list {
50			struct double_list *next;
51			struct double_list *prev;
52			char *data;
53			};
54
55			// Return the first item from the list, advancing the list (which must be called
56			// as &list)
57			static
58			void TOY_llist_pop(void list)
59	niro	532	{
60	niro	1179	// I'd use a void ** for the argument, and even accept the typecast in all
61			// callers as documentation you need the &, except the stupid compiler
62			// would then scream about type-punned pointers. Screw it.
63			void llist = (void )list;
64			void next = (void )*llist;
65			llist = next;
66
67			return (void *)next;
68			}
69
70			// Free all the elements of a linked list
71			// if freeit!=NULL call freeit() on each element before freeing it.
72			static
73			void TOY_llist_free(void list, void (freeit)(void *data))
74			{
75			while (list) {
76			void *pop = TOY_llist_pop(&list);
77			if (freeit) freeit(pop);
78			else free(pop);
79
80			// End doubly linked list too.
81			if (list==pop) break;
82			}
83			}
84			//Override bbox's names
85			#define llist_pop TOY_llist_pop
86			#define llist_free TOY_llist_free
87
88			// Add an entry to the end off a doubly linked list
89			static
90			struct double_list dlist_add(struct double_list list, char data)
91			{
92			struct double_list *line = xmalloc(sizeof(struct double_list));
93
94			line->data = data;
95			if (*list) {
96			line->next = *list;
97			line->prev = (*list)->prev;
98			(*list)->prev->next = line;
99			(*list)->prev = line;
100			} else *list = line->next = line->prev = line;
101
102			return line;
103			}
104
105			// Ensure entire path exists.
106			// If mode != -1 set permissions on newly created dirs.
107			// Requires that path string be writable (for temporary null terminators).
108			static
109			void xmkpath(char *path, int mode)
110			{
111			char *p, old;
112			mode_t mask;
113			int rc;
114			struct stat st;
115
116			for (p = path; ; p++) {
117			if (!p \|\| p == '/') {
118			old = *p;
119			*p = rc = 0;
120			if (stat(path, &st) \|\| !S_ISDIR(st.st_mode)) {
121			if (mode != -1) {
122			mask = umask(0);
123			rc = mkdir(path, mode);
124			umask(mask);
125			} else rc = mkdir(path, 0777);
126			}
127			*p = old;
128			if(rc) bb_perror_msg_and_die("mkpath '%s'", path);
129	niro	532	}
130	niro	1179	if (!*p) break;
131	niro	532	}
132			}
133
134	niro	1179	// Slow, but small.
135			static
136			char get_rawline(int fd, long plen, char end)
137	niro	532	{
138	niro	1179	char c, *buf = NULL;
139			long len = 0;
140	niro	532
141	niro	1179	for (;;) {
142			if (1>read(fd, &c, 1)) break;
143			if (!(len & 63)) buf=xrealloc(buf, len+65);
144			if ((buf[len++]=c) == end) break;
145			}
146			if (buf) buf[len]=0;
147			if (plen) *plen = len;
148	niro	532
149	niro	1179	return buf;
150			}
151
152			static
153			char *get_line(int fd)
154			{
155			long len;
156			char *buf = get_rawline(fd, &len, '\n');
157
158			if (buf && buf[--len]=='\n') buf[len]=0;
159
160			return buf;
161			}
162
163			// Copy the rest of in to out and close both files.
164			static
165			void xsendfile(int in, int out)
166			{
167			long len;
168			char buf[4096];
169
170			if (in<0) return;
171			for (;;) {
172			len = safe_read(in, buf, 4096);
173			if (len<1) break;
174			xwrite(out, buf, len);
175			}
176			}
177
178			// Copy the rest of the data and replace the original with the copy.
179			static
180			void replace_tempfile(int fdin, int fdout, char **tempname)
181			{
182			char temp = xstrdup(tempname);
183
184			temp[strlen(temp)-6]=0;
185			if (fdin != -1) {
186			xsendfile(fdin, fdout);
187			xclose(fdin);
188			}
189			xclose(fdout);
190			rename(*tempname, temp);
191			free(*tempname);
192			free(temp);
193			*tempname = NULL;
194			}
195
196			// Open a temporary file to copy an existing file into.
197			static
198			int copy_tempfile(int fdin, char name, char *tempname)
199			{
200			struct stat statbuf;
201			int fd;
202
203			*tempname = xasprintf("%sXXXXXX", name);
204			fd = mkstemp(*tempname);
205			if(-1 == fd) bb_perror_msg_and_die("no temp file");
206
207			// Set permissions of output file
208			fstat(fdin, &statbuf);
209			fchmod(fd, statbuf.st_mode);
210
211			return fd;
212			}
213
214			// Abort the copy and delete the temporary file.
215			static
216			void delete_tempfile(int fdin, int fdout, char **tempname)
217			{
218			close(fdin);
219			close(fdout);
220			unlink(*tempname);
221			free(*tempname);
222			*tempname = NULL;
223			}
224
225
226
227			struct globals {
228			char *infile;
229			long prefix;
230
231			struct double_list *current_hunk;
232			long oldline, oldlen, newline, newlen;
233			long linenum;
234			int context, state, filein, fileout, filepatch, hunknum;
235			char *tempname;
236
237			// was toys.foo:
238			int exitval;
239			};
240			#define TT (*ptr_to_globals)
241			#define INIT_TT() do { \
242			SET_PTR_TO_GLOBALS(xzalloc(sizeof(TT))); \
243			} while (0)
244
245
246			#define FLAG_STR "Rup:i:Nx"
247			/* FLAG_REVERSE must be == 1! Code uses this fact. */
248			#define FLAG_REVERSE (1 << 0)
249			#define FLAG_u (1 << 1)
250			#define FLAG_PATHLEN (1 << 2)
251			#define FLAG_INPUT (1 << 3)
252			#define FLAG_IGNORE (1 << 4)
253			//non-standard:
254			#define FLAG_DEBUG (1 << 5)
255
256			// Dispose of a line of input, either by writing it out or discarding it.
257
258			// state < 2: just free
259			// state = 2: write whole line to stderr
260			// state = 3: write whole line to fileout
261			// state > 3: write line+1 to fileout when *line != state
262
263			#define PATCH_DEBUG (option_mask32 & FLAG_DEBUG)
264
265			static void do_line(void *data)
266			{
267			struct double_list dlist = (struct double_list )data;
268
269			if (TT.state>1 && *dlist->data != TT.state)
270			fdprintf(TT.state == 2 ? 2 : TT.fileout,
271			"%s\n", dlist->data+(TT.state>3 ? 1 : 0));
272
273			if (PATCH_DEBUG) fdprintf(2, "DO %d: %s\n", TT.state, dlist->data);
274
275			free(dlist->data);
276			free(data);
277			}
278
279			static void finish_oldfile(void)
280			{
281			if (TT.tempname) replace_tempfile(TT.filein, TT.fileout, &TT.tempname);
282			TT.fileout = TT.filein = -1;
283			}
284
285			static void fail_hunk(void)
286			{
287			if (!TT.current_hunk) return;
288			TT.current_hunk->prev->next = 0;
289
290			fdprintf(2, "Hunk %d FAILED %ld/%ld.\n", TT.hunknum, TT.oldline, TT.newline);
291			TT.exitval = 1;
292
293			// If we got to this point, we've seeked to the end. Discard changes to
294			// this file and advance to next file.
295
296			TT.state = 2;
297			llist_free(TT.current_hunk, do_line);
298			TT.current_hunk = NULL;
299			delete_tempfile(TT.filein, TT.fileout, &TT.tempname);
300			TT.state = 0;
301			}
302
303			// Given a hunk of a unified diff, make the appropriate change to the file.
304			// This does not use the location information, but instead treats a hunk
305			// as a sort of regex. Copies data from input to output until it finds
306			// the change to be made, then outputs the changed data and returns.
307			// (Finding EOF first is an error.) This is a single pass operation, so
308			// multiple hunks must occur in order in the file.
309
310			static int apply_one_hunk(void)
311			{
312			struct double_list plist, buf = NULL, *check;
313			int matcheof = 0, reverse = option_mask32 & FLAG_REVERSE, backwarn = 0;
314			/* Do we try "dummy" revert to check whether
315			* to silently skip this hunk? Used to implement -N.
316			*/
317			int dummy_revert = 0;
318
319			// Break doubly linked list so we can use singly linked traversal function.
320			TT.current_hunk->prev->next = NULL;
321
322			// Match EOF if there aren't as many ending context lines as beginning
323			for (plist = TT.current_hunk; plist; plist = plist->next) {
324			if (plist->data[0]==' ') matcheof++;
325			else matcheof = 0;
326			if (PATCH_DEBUG) fdprintf(2, "HUNK:%s\n", plist->data);
327			}
328			matcheof = matcheof < TT.context;
329
330			if (PATCH_DEBUG) fdprintf(2,"MATCHEOF=%c\n", matcheof ? 'Y' : 'N');
331
332			// Loop through input data searching for this hunk. Match all context
333			// lines and all lines to be removed until we've found the end of a
334			// complete hunk.
335			plist = TT.current_hunk;
336			buf = NULL;
337			if (TT.context) for (;;) {
338			char *data = get_line(TT.filein);
339
340			TT.linenum++;
341
342			// Figure out which line of hunk to compare with next. (Skip lines
343			// of the hunk we'd be adding.)
344			while (plist && *plist->data == "+-"[reverse]) {
345			if (data && !strcmp(data, plist->data+1)) {
346			if (!backwarn) {
347			backwarn++;
348			if (option_mask32 & FLAG_IGNORE) {
349			dummy_revert = 1;
350			reverse ^= 1;
351			continue;
352			}
353			fdprintf(2,"Possibly reversed hunk %d at %ld\n",
354			TT.hunknum, TT.linenum);
355			}
356			}
357			plist = plist->next;
358	niro	816	}
359	niro	1179
360			// Is this EOF?
361			if (!data) {
362			if (PATCH_DEBUG) fdprintf(2, "INEOF\n");
363
364			// Does this hunk need to match EOF?
365			if (!plist && matcheof) break;
366
367			// File ended before we found a place for this hunk.
368			fail_hunk();
369			goto done;
370			} else if (PATCH_DEBUG) fdprintf(2, "IN: %s\n", data);
371			check = dlist_add(&buf, data);
372
373			// Compare this line with next expected line of hunk.
374			// todo: teach the strcmp() to ignore whitespace.
375
376			// A match can fail because the next line doesn't match, or because
377			// we hit the end of a hunk that needed EOF, and this isn't EOF.
378
379			// If match failed, flush first line of buffered data and
380			// recheck buffered data for a new match until we find one or run
381			// out of buffer.
382
383			for (;;) {
384			if (!plist \|\| strcmp(check->data, plist->data+1)) {
385			// Match failed. Write out first line of buffered data and
386			// recheck remaining buffered data for a new match.
387
388			if (PATCH_DEBUG)
389			fdprintf(2, "NOT: %s\n", plist->data);
390
391			TT.state = 3;
392			check = llist_pop(&buf);
393			check->prev->next = buf;
394			buf->prev = check->prev;
395			do_line(check);
396			plist = TT.current_hunk;
397
398			// If we've reached the end of the buffer without confirming a
399			// match, read more lines.
400			if (check==buf) {
401			buf = 0;
402			break;
403			}
404			check = buf;
405			} else {
406			if (PATCH_DEBUG)
407			fdprintf(2, "MAYBE: %s\n", plist->data);
408			// This line matches. Advance plist, detect successful match.
409			plist = plist->next;
410			if (!plist && !matcheof) goto out;
411			check = check->next;
412			if (check == buf) break;
413			}
414			}
415	niro	532	}
416	niro	1179	out:
417			// We have a match. Emit changed data.
418			TT.state = "-+"[reverse ^ dummy_revert];
419			llist_free(TT.current_hunk, do_line);
420			TT.current_hunk = NULL;
421			TT.state = 1;
422			done:
423			if (buf) {
424			buf->prev->next = NULL;
425			llist_free(buf, do_line);
426			}
427
428			return TT.state;
429	niro	532	}
430
431	niro	1179	// Read a patch file and find hunks, opening/creating/deleting files.
432			// Call apply_one_hunk() on each hunk.
433
434			// state 0: Not in a hunk, look for +++.
435			// state 1: Found +++ file indicator, look for @@
436			// state 2: In hunk: counting initial context lines
437			// state 3: In hunk: getting body
438
439	niro	816	int patch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
440			int patch_main(int argc UNUSED_PARAM, char **argv)
441	niro	532	{
442	niro	1179	int opts;
443			int reverse, state = 0;
444			char oldname = NULL, newname = NULL;
445			char opt_p, opt_i;
446	niro	532
447	niro	1179	INIT_TT();
448
449			opts = getopt32(argv, FLAG_STR, &opt_p, &opt_i);
450			argv += optind;
451			reverse = opts & FLAG_REVERSE;
452			TT.prefix = (opts & FLAG_PATHLEN) ? xatoi(opt_p) : 0; // can be negative!
453			TT.filein = TT.fileout = -1;
454			if (opts & FLAG_INPUT) {
455			TT.filepatch = xopen_stdin(opt_i);
456			} else {
457			if (argv[0] && argv[1]) {
458			TT.filepatch = xopen_stdin(argv[1]);
459			}
460	niro	532	}
461	niro	1179	if (argv[0]) {
462			oldname = xstrdup(argv[0]);
463			newname = xstrdup(argv[0]);
464			}
465	niro	532
466	niro	1179	// Loop through the lines in the patch
467			for(;;) {
468			char *patchline;
469	niro	532
470	niro	1179	patchline = get_line(TT.filepatch);
471			if (!patchline) break;
472	niro	532
473	niro	1179	// Other versions of patch accept damaged patches,
474			// so we need to also.
475			if (!*patchline) {
476			free(patchline);
477			patchline = xstrdup(" ");
478	niro	532	}
479
480	niro	1179	// Are we assembling a hunk?
481			if (state >= 2) {
482			if (patchline==' ' \|\| patchline=='+' \|\| *patchline=='-') {
483			dlist_add(&TT.current_hunk, patchline);
484	niro	984
485	niro	1179	if (*patchline != '+') TT.oldlen--;
486			if (*patchline != '-') TT.newlen--;
487	niro	532
488	niro	1179	// Context line?
489			if (*patchline==' ' && state==2) TT.context++;
490			else state=3;
491	niro	532
492	niro	1179	// If we've consumed all expected hunk lines, apply the hunk.
493	niro	532
494	niro	1179	if (!TT.oldlen && !TT.newlen) state = apply_one_hunk();
495			continue;
496	niro	532	}
497	niro	1179	fail_hunk();
498			state = 0;
499			continue;
500			}
501
502			// Open a new file?
503			if (!strncmp("--- ", patchline, 4) \|\| !strncmp("+++ ", patchline, 4)) {
504			char s, *name = reverse ? &newname : &oldname;
505			int i;
506
507			if (*patchline == '+') {
508			name = reverse ? &oldname : &newname;
509			state = 1;
510	niro	816	}
511	niro	532
512	niro	1179	finish_oldfile();
513
514			if (!argv[0]) {
515			free(*name);
516			// Trim date from end of filename (if any). We don't care.
517			for (s = patchline+4; s && s!='\t'; s++)
518			if (*s=='\\' && s[1]) s++;
519			i = atoi(s);
520			if (i>1900 && i<=1970)
521			*name = xstrdup("/dev/null");
522			else {
523			*s = 0;
524			*name = xstrdup(patchline+4);
525	niro	532	}
526			}
527
528	niro	1179	// We defer actually opening the file because svn produces broken
529			// patches that don't signal they want to create a new file the
530			// way the patch man page says, so you have to read the first hunk
531			// and _guess_.
532
533			// Start a new hunk? Usually @@ -oldline,oldlen +newline,newlen @@
534			// but a missing ,value means the value is 1.
535			} else if (state == 1 && !strncmp("@@ -", patchline, 4)) {
536			int i;
537			char *s = patchline+4;
538
539			// Read oldline[,oldlen] +newline[,newlen]
540
541			TT.oldlen = TT.newlen = 1;
542			TT.oldline = strtol(s, &s, 10);
543			if (*s == ',') TT.oldlen=strtol(s+1, &s, 10);
544			TT.newline = strtol(s+2, &s, 10);
545			if (*s == ',') TT.newlen = strtol(s+1, &s, 10);
546
547			TT.context = 0;
548			state = 2;
549
550			// If this is the first hunk, open the file.
551			if (TT.filein == -1) {
552			int oldsum, newsum, del = 0;
553			char *name;
554
555			oldsum = TT.oldline + TT.oldlen;
556			newsum = TT.newline + TT.newlen;
557
558			name = reverse ? oldname : newname;
559
560			// We're deleting oldname if new file is /dev/null (before -p)
561			// or if new hunk is empty (zero context) after patching
562			if (!strcmp(name, "/dev/null") \|\| !(reverse ? oldsum : newsum))
563			{
564			name = reverse ? newname : oldname;
565			del++;
566	niro	984	}
567	niro	1179
568			// handle -p path truncation.
569			for (i=0, s = name; *s;) {
570			if ((option_mask32 & FLAG_PATHLEN) && TT.prefix == i) break;
571			if (*(s++)=='/') {
572			name = s;
573			i++;
574			}
575	niro	816	}
576	niro	1179
577			if (del) {
578			printf("removing %s\n", name);
579			xunlink(name);
580			state = 0;
581			// If we've got a file to open, do so.
582			} else if (!(option_mask32 & FLAG_PATHLEN) \|\| i <= TT.prefix) {
583			// If the old file was null, we're creating a new one.
584			if (!strcmp(oldname, "/dev/null") \|\| !oldsum) {
585			printf("creating %s\n", name);
586			s = strrchr(name, '/');
587			if (s) {
588			*s = 0;
589			xmkpath(name, -1);
590			*s = '/';
591	niro	532	}
592	niro	1179	TT.filein = xopen3(name, O_CREAT\|O_EXCL\|O_RDWR, 0666);
593			} else {
594			printf("patching file %s\n", name);
595			TT.filein = xopen(name, O_RDWR);
596	niro	532	}
597	niro	1179	TT.fileout = copy_tempfile(TT.filein, name, &TT.tempname);
598			TT.linenum = 0;
599			TT.hunknum = 0;
600	niro	816	}
601	niro	1179	}
602	niro	532
603	niro	1179	TT.hunknum++;
604
605			continue;
606	niro	532	}
607	niro	1179
608			// If we didn't continue above, discard this line.
609			free(patchline);
610			}
611
612			finish_oldfile();
613
614			if (ENABLE_FEATURE_CLEAN_UP) {
615			close(TT.filepatch);
616			free(oldname);
617			free(newname);
618			}
619
620			return TT.exitval;
621	niro	532	}