busybox/editors/patch.c

/* vi: set sw=4 ts=4: */
/*
 *  busybox patch applet to handle the unified diff format.
 *  Copyright (C) 2003 Glenn McGrath <bug1@iinet.net.au>
 *
 *  Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
 *
 *  This applet is written to work with patches generated by GNU diff,
 *  where there is equivalent functionality busybox patch shall behave
 *  as per GNU patch.
 *
 *  There is a SUSv3 specification for patch, however it looks to be
 *  incomplete, it doesnt even mention unified diff format.
 *  http://www.opengroup.org/onlinepubs/007904975/utilities/patch.html
 *
 *  Issues
 *   - Non-interactive
 *   - Patches must apply cleanly or patch (not just one hunk) will fail.
 *   - Reject file isnt saved
 */

#include <getopt.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include "busybox.h"

static unsigned int copy_lines(FILE *src_stream, FILE *dest_stream, const unsigned int lines_count)
{
	unsigned int i = 0;

	while (src_stream && (i < lines_count)) {
		char *line;
		line = xmalloc_fgets(src_stream);
		if (line == NULL) {
			break;
		}
		if (fputs(line, dest_stream) == EOF) {
			bb_perror_msg_and_die("error writing to new file");
		}
		free(line);

		i++;
	}
	return i;
}

/* If patch_level is -1 it will remove all directory names
 * char *line must be greater than 4 chars
 * returns NULL if the file doesnt exist or error
 * returns malloc'ed filename
 */

static char *extract_filename(char *line, int patch_level)
{
	char *temp, *filename_start_ptr = line + 4;
	int i;

	/* Terminate string at end of source filename */
	temp = strchr(filename_start_ptr, '\t');
	if (temp) *temp = 0;

	/* skip over (patch_level) number of leading directories */
	for (i = 0; i < patch_level; i++) {
		if(!(temp = strchr(filename_start_ptr, '/'))) break;
		filename_start_ptr = temp + 1;
	}

	return xstrdup(filename_start_ptr);
}

static int file_doesnt_exist(const char *filename)
{
	struct stat statbuf;
	return stat(filename, &statbuf);
}

int patch_main(int argc, char **argv)
{
	int patch_level = -1;
	char *patch_line;
	int ret;
	FILE *patch_file = NULL;

	{
		char *p, *i;
		ret = getopt32(argc, argv, "p:i:", &p, &i);
		if (ret & 1)
			patch_level = xatol_range(p, -1, USHRT_MAX);
		if (ret & 2) {
			patch_file = xfopen(i, "r");
		} else {
			patch_file = stdin;
		}
		ret = 0;
	}

	patch_line = xmalloc_fgets(patch_file);
	while (patch_line) {
		FILE *src_stream;
		FILE *dst_stream;
		char *original_filename;
		char *new_filename;
		char *backup_filename;
		unsigned int src_cur_line = 1;
		unsigned int dest_cur_line = 0;
		unsigned int dest_beg_line;
		unsigned int bad_hunk_count = 0;
		unsigned int hunk_count = 0;
		char copy_trailing_lines_flag = 0;

		/* Skip everything upto the "---" marker
		 * No need to parse the lines "Only in <dir>", and "diff <args>"
		 */
		while (patch_line && strncmp(patch_line, "--- ", 4) != 0) {
			free(patch_line);
			patch_line = xmalloc_fgets(patch_file);
		}
		/* FIXME: patch_line NULL check?? */

		/* Extract the filename used before the patch was generated */
		original_filename = extract_filename(patch_line, patch_level);
		free(patch_line);

		patch_line = xmalloc_fgets(patch_file);
		/* FIXME: NULL check?? */
		if (strncmp(patch_line, "+++ ", 4) != 0) {
			ret = 2;
			bb_error_msg("invalid patch");
			continue;
		}
		new_filename = extract_filename(patch_line, patch_level);
		free(patch_line);

		if (file_doesnt_exist(new_filename)) {
			char *line_ptr;
			/* Create leading directories */
			line_ptr = strrchr(new_filename, '/');
			if (line_ptr) {
				*line_ptr = '\0';
				bb_make_directory(new_filename, -1, FILEUTILS_RECUR);
				*line_ptr = '/';
			}
			dst_stream = xfopen(new_filename, "w+");
			backup_filename = NULL;
		} else {
			backup_filename = xmalloc(strlen(new_filename) + 6);
			strcpy(backup_filename, new_filename);
			strcat(backup_filename, ".orig");
			if (rename(new_filename, backup_filename) == -1) {
				bb_perror_msg_and_die("cannot create file %s",
						backup_filename);
			}
			dst_stream = xfopen(new_filename, "w");
		}

		if ((backup_filename == NULL) || file_doesnt_exist(original_filename)) {
			src_stream = NULL;
		} else {
			if (strcmp(original_filename, new_filename) == 0) {
				src_stream = xfopen(backup_filename, "r");
			} else {
				src_stream = xfopen(original_filename, "r");
			}
		}

		printf("patching file %s\n", new_filename);

		/* Handle each hunk */
		patch_line = xmalloc_fgets(patch_file);
		while (patch_line) {
			unsigned int count;
			unsigned int src_beg_line;
			unsigned int unused;
			unsigned int hunk_offset_start = 0;
			int hunk_error = 0;

			/* This bit should be improved */
			if ((sscanf(patch_line, "@@ -%d,%d +%d,%d @@", &src_beg_line, &unused, &dest_beg_line, &unused) != 4) &&
				(sscanf(patch_line, "@@ -%d,%d +%d @@", &src_beg_line, &unused, &dest_beg_line) != 3) &&
				(sscanf(patch_line, "@@ -%d +%d,%d @@", &src_beg_line, &dest_beg_line, &unused) != 3)) {
				/* No more hunks for this file */
				break;
			}
			free(patch_line);
			hunk_count++;

			if (src_beg_line && dest_beg_line) {
				/* Copy unmodified lines upto start of hunk */
				/* src_beg_line will be 0 if its a new file */
				count = src_beg_line - src_cur_line;
				if (copy_lines(src_stream, dst_stream, count) != count) {
					bb_error_msg_and_die("bad src file");
				}
				src_cur_line += count;
				dest_cur_line += count;
				copy_trailing_lines_flag = 1;
			}
			hunk_offset_start = src_cur_line;

			while ((patch_line = xmalloc_fgets(patch_file)) != NULL) {
				if ((*patch_line == '-') || (*patch_line == ' ')) {
					char *src_line = NULL;
					if (src_stream) {
						src_line = xmalloc_fgets(src_stream);
						if (!src_line) {
							hunk_error++;
							break;
						} else {
							src_cur_line++;
						}
						if (strcmp(src_line, patch_line + 1) != 0) {
							bb_error_msg("hunk #%d FAILED at %d", hunk_count, hunk_offset_start);
							hunk_error++;
							free(patch_line);
							/* Probably need to find next hunk, etc... */
							/* but for now we just bail out */
							patch_line = NULL;
							break;
						}
						free(src_line);
					}
					if (*patch_line == ' ') {
						fputs(patch_line + 1, dst_stream);
						dest_cur_line++;
					}
				} else if (*patch_line == '+') {
					fputs(patch_line + 1, dst_stream);
					dest_cur_line++;
				} else {
					break;
				}
				free(patch_line);
			}
			if (hunk_error) {
				bad_hunk_count++;
			}
		}

		/* Cleanup last patched file */
		if (copy_trailing_lines_flag) {
			copy_lines(src_stream, dst_stream, -1);
		}
		if (src_stream) {
			fclose(src_stream);
		}
		if (dst_stream) {
			fclose(dst_stream);
		}
		if (bad_hunk_count) {
			if (!ret) {
				ret = 1;
			}
			bb_error_msg("%d out of %d hunk FAILED", bad_hunk_count, hunk_count);
		} else {
			/* It worked, we can remove the backup */
			if (backup_filename) {
				unlink(backup_filename);
			}
			if ((dest_cur_line == 0) || (dest_beg_line == 0)) {
				/* The new patched file is empty, remove it */
				if (unlink(new_filename) == -1) {
					bb_perror_msg_and_die("cannot remove file %s", new_filename);
				}
				if (unlink(original_filename) == -1) {
					bb_perror_msg_and_die("cannot remove original file %s", new_filename);
				}
			}
		}
	}

	/* 0 = SUCCESS
	 * 1 = Some hunks failed
	 * 2 = More serious problems
	 */
	return ret;
}
1	niro	532	/* vi: set sw=4 ts=4: */
2			/*
3			* busybox patch applet to handle the unified diff format.
4			* Copyright (C) 2003 Glenn McGrath <bug1@iinet.net.au>
5			*
6			* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
7			*
8			* This applet is written to work with patches generated by GNU diff,
9			* where there is equivalent functionality busybox patch shall behave
10			* as per GNU patch.
11			*
12			* There is a SUSv3 specification for patch, however it looks to be
13			* incomplete, it doesnt even mention unified diff format.
14			* http://www.opengroup.org/onlinepubs/007904975/utilities/patch.html
15			*
16			* Issues
17			* - Non-interactive
18			* - Patches must apply cleanly or patch (not just one hunk) will fail.
19			* - Reject file isnt saved
20			*/
21
22			#include <getopt.h>
23			#include <string.h>
24			#include <stdlib.h>
25			#include <unistd.h>
26			#include "busybox.h"
27
28			static unsigned int copy_lines(FILE src_stream, FILE dest_stream, const unsigned int lines_count)
29			{
30			unsigned int i = 0;
31
32			while (src_stream && (i < lines_count)) {
33			char *line;
34			line = xmalloc_fgets(src_stream);
35			if (line == NULL) {
36			break;
37			}
38			if (fputs(line, dest_stream) == EOF) {
39			bb_perror_msg_and_die("error writing to new file");
40			}
41			free(line);
42
43			i++;
44			}
45			return i;
46			}
47
48			/* If patch_level is -1 it will remove all directory names
49			* char *line must be greater than 4 chars
50			* returns NULL if the file doesnt exist or error
51			* returns malloc'ed filename
52			*/
53
54			static char extract_filename(char line, int patch_level)
55			{
56			char temp, filename_start_ptr = line + 4;
57			int i;
58
59			/* Terminate string at end of source filename */
60			temp = strchr(filename_start_ptr, '\t');
61			if (temp) *temp = 0;
62
63			/* skip over (patch_level) number of leading directories */
64			for (i = 0; i < patch_level; i++) {
65			if(!(temp = strchr(filename_start_ptr, '/'))) break;
66			filename_start_ptr = temp + 1;
67			}
68
69			return xstrdup(filename_start_ptr);
70			}
71
72			static int file_doesnt_exist(const char *filename)
73			{
74			struct stat statbuf;
75			return stat(filename, &statbuf);
76			}
77
78			int patch_main(int argc, char **argv)
79			{
80			int patch_level = -1;
81			char *patch_line;
82			int ret;
83			FILE *patch_file = NULL;
84
85			{
86			char p, i;
87			ret = getopt32(argc, argv, "p:i:", &p, &i);
88			if (ret & 1)
89			patch_level = xatol_range(p, -1, USHRT_MAX);
90			if (ret & 2) {
91			patch_file = xfopen(i, "r");
92			} else {
93			patch_file = stdin;
94			}
95			ret = 0;
96			}
97
98			patch_line = xmalloc_fgets(patch_file);
99			while (patch_line) {
100			FILE *src_stream;
101			FILE *dst_stream;
102			char *original_filename;
103			char *new_filename;
104			char *backup_filename;
105			unsigned int src_cur_line = 1;
106			unsigned int dest_cur_line = 0;
107			unsigned int dest_beg_line;
108			unsigned int bad_hunk_count = 0;
109			unsigned int hunk_count = 0;
110			char copy_trailing_lines_flag = 0;
111
112			/* Skip everything upto the "---" marker
113			* No need to parse the lines "Only in <dir>", and "diff <args>"
114			*/
115			while (patch_line && strncmp(patch_line, "--- ", 4) != 0) {
116			free(patch_line);
117			patch_line = xmalloc_fgets(patch_file);
118			}
119			/* FIXME: patch_line NULL check?? */
120
121			/* Extract the filename used before the patch was generated */
122			original_filename = extract_filename(patch_line, patch_level);
123			free(patch_line);
124
125			patch_line = xmalloc_fgets(patch_file);
126			/* FIXME: NULL check?? */
127			if (strncmp(patch_line, "+++ ", 4) != 0) {
128			ret = 2;
129			bb_error_msg("invalid patch");
130			continue;
131			}
132			new_filename = extract_filename(patch_line, patch_level);
133			free(patch_line);
134
135			if (file_doesnt_exist(new_filename)) {
136			char *line_ptr;
137			/* Create leading directories */
138			line_ptr = strrchr(new_filename, '/');
139			if (line_ptr) {
140			*line_ptr = '\0';
141			bb_make_directory(new_filename, -1, FILEUTILS_RECUR);
142			*line_ptr = '/';
143			}
144			dst_stream = xfopen(new_filename, "w+");
145			backup_filename = NULL;
146			} else {
147			backup_filename = xmalloc(strlen(new_filename) + 6);
148			strcpy(backup_filename, new_filename);
149			strcat(backup_filename, ".orig");
150			if (rename(new_filename, backup_filename) == -1) {
151			bb_perror_msg_and_die("cannot create file %s",
152			backup_filename);
153			}
154			dst_stream = xfopen(new_filename, "w");
155			}
156
157			if ((backup_filename == NULL) \|\| file_doesnt_exist(original_filename)) {
158			src_stream = NULL;
159			} else {
160			if (strcmp(original_filename, new_filename) == 0) {
161			src_stream = xfopen(backup_filename, "r");
162			} else {
163			src_stream = xfopen(original_filename, "r");
164			}
165			}
166
167			printf("patching file %s\n", new_filename);
168
169			/* Handle each hunk */
170			patch_line = xmalloc_fgets(patch_file);
171			while (patch_line) {
172			unsigned int count;
173			unsigned int src_beg_line;
174			unsigned int unused;
175			unsigned int hunk_offset_start = 0;
176			int hunk_error = 0;
177
178			/* This bit should be improved */
179			if ((sscanf(patch_line, "@@ -%d,%d +%d,%d @@", &src_beg_line, &unused, &dest_beg_line, &unused) != 4) &&
180			(sscanf(patch_line, "@@ -%d,%d +%d @@", &src_beg_line, &unused, &dest_beg_line) != 3) &&
181			(sscanf(patch_line, "@@ -%d +%d,%d @@", &src_beg_line, &dest_beg_line, &unused) != 3)) {
182			/* No more hunks for this file */
183			break;
184			}
185			free(patch_line);
186			hunk_count++;
187
188			if (src_beg_line && dest_beg_line) {
189			/* Copy unmodified lines upto start of hunk */
190			/* src_beg_line will be 0 if its a new file */
191			count = src_beg_line - src_cur_line;
192			if (copy_lines(src_stream, dst_stream, count) != count) {
193			bb_error_msg_and_die("bad src file");
194			}
195			src_cur_line += count;
196			dest_cur_line += count;
197			copy_trailing_lines_flag = 1;
198			}
199			hunk_offset_start = src_cur_line;
200
201			while ((patch_line = xmalloc_fgets(patch_file)) != NULL) {
202			if ((patch_line == '-') \|\| (patch_line == ' ')) {
203			char *src_line = NULL;
204			if (src_stream) {
205			src_line = xmalloc_fgets(src_stream);
206			if (!src_line) {
207			hunk_error++;
208			break;
209			} else {
210			src_cur_line++;
211			}
212			if (strcmp(src_line, patch_line + 1) != 0) {
213			bb_error_msg("hunk #%d FAILED at %d", hunk_count, hunk_offset_start);
214			hunk_error++;
215			free(patch_line);
216			/* Probably need to find next hunk, etc... */
217			/* but for now we just bail out */
218			patch_line = NULL;
219			break;
220			}
221			free(src_line);
222			}
223			if (*patch_line == ' ') {
224			fputs(patch_line + 1, dst_stream);
225			dest_cur_line++;
226			}
227			} else if (*patch_line == '+') {
228			fputs(patch_line + 1, dst_stream);
229			dest_cur_line++;
230			} else {
231			break;
232			}
233			free(patch_line);
234			}
235			if (hunk_error) {
236			bad_hunk_count++;
237			}
238			}
239
240			/* Cleanup last patched file */
241			if (copy_trailing_lines_flag) {
242			copy_lines(src_stream, dst_stream, -1);
243			}
244			if (src_stream) {
245			fclose(src_stream);
246			}
247			if (dst_stream) {
248			fclose(dst_stream);
249			}
250			if (bad_hunk_count) {
251			if (!ret) {
252			ret = 1;
253			}
254			bb_error_msg("%d out of %d hunk FAILED", bad_hunk_count, hunk_count);
255			} else {
256			/* It worked, we can remove the backup */
257			if (backup_filename) {
258			unlink(backup_filename);
259			}
260			if ((dest_cur_line == 0) \|\| (dest_beg_line == 0)) {
261			/* The new patched file is empty, remove it */
262			if (unlink(new_filename) == -1) {
263			bb_perror_msg_and_die("cannot remove file %s", new_filename);
264			}
265			if (unlink(original_filename) == -1) {
266			bb_perror_msg_and_die("cannot remove original file %s", new_filename);
267			}
268			}
269			}
270			}
271
272			/* 0 = SUCCESS
273			* 1 = Some hunks failed
274			* 2 = More serious problems
275			*/
276			return ret;
277			}