Contents of /tags/mkinitrd-6_1_12/busybox/editors/patch.c
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Tue Nov 17 21:24:51 2009 UTC (14 years, 10 months ago) by niro
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File size: 7097 byte(s)
Tue Nov 17 21:24:51 2009 UTC (14 years, 10 months ago) by niro
File MIME type: text/plain
File size: 7097 byte(s)
tagged 'mkinitrd-6_1_12'
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * busybox patch applet to handle the unified diff format. |
4 | * Copyright (C) 2003 Glenn McGrath |
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 "libbb.h" |
23 | |
24 | static unsigned copy_lines(FILE *src_stream, FILE *dst_stream, unsigned lines_count) |
25 | { |
26 | while (src_stream && lines_count) { |
27 | char *line; |
28 | line = xmalloc_fgets(src_stream); |
29 | if (line == NULL) { |
30 | break; |
31 | } |
32 | if (fputs(line, dst_stream) == EOF) { |
33 | bb_perror_msg_and_die("error writing to new file"); |
34 | } |
35 | free(line); |
36 | lines_count--; |
37 | } |
38 | return lines_count; |
39 | } |
40 | |
41 | /* If patch_level is -1 it will remove all directory names |
42 | * char *line must be greater than 4 chars |
43 | * returns NULL if the file doesnt exist or error |
44 | * returns malloc'ed filename |
45 | * NB: frees 1st argument! |
46 | */ |
47 | static char *extract_filename(char *line, int patch_level, const char *pat) |
48 | { |
49 | char *temp = NULL, *filename_start_ptr = line + 4; |
50 | |
51 | if (strncmp(line, pat, 4) == 0) { |
52 | /* Terminate string at end of source filename */ |
53 | line[strcspn(line, "\t\n\r")] = '\0'; |
54 | |
55 | /* Skip over (patch_level) number of leading directories */ |
56 | while (patch_level--) { |
57 | temp = strchr(filename_start_ptr, '/'); |
58 | if (!temp) |
59 | break; |
60 | filename_start_ptr = temp + 1; |
61 | } |
62 | temp = xstrdup(filename_start_ptr); |
63 | } |
64 | free(line); |
65 | return temp; |
66 | } |
67 | |
68 | int patch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
69 | int patch_main(int argc UNUSED_PARAM, char **argv) |
70 | { |
71 | struct stat saved_stat; |
72 | char *patch_line; |
73 | FILE *patch_file; |
74 | int patch_level; |
75 | int ret = 0; |
76 | char plus = '+'; |
77 | |
78 | xfunc_error_retval = 2; |
79 | { |
80 | const char *p = "-1"; |
81 | const char *i = "-"; /* compat */ |
82 | if (getopt32(argv, "p:i:R", &p, &i) & 4) |
83 | plus = '-'; |
84 | patch_level = xatoi(p); /* can be negative! */ |
85 | patch_file = xfopen_stdin(i); |
86 | } |
87 | |
88 | patch_line = xmalloc_fgetline(patch_file); |
89 | while (patch_line) { |
90 | FILE *src_stream; |
91 | FILE *dst_stream; |
92 | //char *old_filename; |
93 | char *new_filename; |
94 | char *backup_filename; |
95 | unsigned src_cur_line = 1; |
96 | unsigned dst_cur_line = 0; |
97 | unsigned dst_beg_line; |
98 | unsigned bad_hunk_count = 0; |
99 | unsigned hunk_count = 0; |
100 | smallint copy_trailing_lines_flag = 0; |
101 | |
102 | /* Skip everything upto the "---" marker |
103 | * No need to parse the lines "Only in <dir>", and "diff <args>" |
104 | */ |
105 | do { |
106 | /* Extract the filename used before the patch was generated */ |
107 | new_filename = extract_filename(patch_line, patch_level, "--- "); |
108 | // was old_filename above |
109 | patch_line = xmalloc_fgetline(patch_file); |
110 | if (!patch_line) goto quit; |
111 | } while (!new_filename); |
112 | free(new_filename); // "source" filename is irrelevant |
113 | |
114 | new_filename = extract_filename(patch_line, patch_level, "+++ "); |
115 | if (!new_filename) { |
116 | bb_error_msg_and_die("invalid patch"); |
117 | } |
118 | |
119 | /* Get access rights from the file to be patched */ |
120 | if (stat(new_filename, &saved_stat) != 0) { |
121 | char *slash = strrchr(new_filename, '/'); |
122 | if (slash) { |
123 | /* Create leading directories */ |
124 | *slash = '\0'; |
125 | bb_make_directory(new_filename, -1, FILEUTILS_RECUR); |
126 | *slash = '/'; |
127 | } |
128 | backup_filename = NULL; |
129 | src_stream = NULL; |
130 | saved_stat.st_mode = 0644; |
131 | } else { |
132 | backup_filename = xasprintf("%s.orig", new_filename); |
133 | xrename(new_filename, backup_filename); |
134 | src_stream = xfopen_for_read(backup_filename); |
135 | } |
136 | dst_stream = xfopen_for_write(new_filename); |
137 | fchmod(fileno(dst_stream), saved_stat.st_mode); |
138 | |
139 | printf("patching file %s\n", new_filename); |
140 | |
141 | /* Handle all hunks for this file */ |
142 | patch_line = xmalloc_fgets(patch_file); |
143 | while (patch_line) { |
144 | unsigned count; |
145 | unsigned src_beg_line; |
146 | unsigned hunk_offset_start; |
147 | unsigned src_last_line = 1; |
148 | unsigned dst_last_line = 1; |
149 | |
150 | if ((sscanf(patch_line, "@@ -%d,%d +%d,%d", &src_beg_line, &src_last_line, &dst_beg_line, &dst_last_line) < 3) |
151 | && (sscanf(patch_line, "@@ -%d +%d,%d", &src_beg_line, &dst_beg_line, &dst_last_line) < 2) |
152 | ) { |
153 | /* No more hunks for this file */ |
154 | break; |
155 | } |
156 | if (plus != '+') { |
157 | /* reverse patch */ |
158 | unsigned tmp = src_last_line; |
159 | src_last_line = dst_last_line; |
160 | dst_last_line = tmp; |
161 | tmp = src_beg_line; |
162 | src_beg_line = dst_beg_line; |
163 | dst_beg_line = tmp; |
164 | } |
165 | hunk_count++; |
166 | |
167 | if (src_beg_line && dst_beg_line) { |
168 | /* Copy unmodified lines upto start of hunk */ |
169 | /* src_beg_line will be 0 if it's a new file */ |
170 | count = src_beg_line - src_cur_line; |
171 | if (copy_lines(src_stream, dst_stream, count)) { |
172 | bb_error_msg_and_die("bad src file"); |
173 | } |
174 | src_cur_line += count; |
175 | dst_cur_line += count; |
176 | copy_trailing_lines_flag = 1; |
177 | } |
178 | src_last_line += hunk_offset_start = src_cur_line; |
179 | dst_last_line += dst_cur_line; |
180 | |
181 | while (1) { |
182 | free(patch_line); |
183 | patch_line = xmalloc_fgets(patch_file); |
184 | if (patch_line == NULL) |
185 | break; /* EOF */ |
186 | if ((*patch_line != '-') && (*patch_line != '+') |
187 | && (*patch_line != ' ') |
188 | ) { |
189 | break; /* End of hunk */ |
190 | } |
191 | if (*patch_line != plus) { /* '-' or ' ' */ |
192 | char *src_line = NULL; |
193 | if (src_cur_line == src_last_line) |
194 | break; |
195 | if (src_stream) { |
196 | src_line = xmalloc_fgets(src_stream); |
197 | if (src_line) { |
198 | int diff = strcmp(src_line, patch_line + 1); |
199 | src_cur_line++; |
200 | free(src_line); |
201 | if (diff) |
202 | src_line = NULL; |
203 | } |
204 | } |
205 | if (!src_line) { |
206 | bb_error_msg("hunk #%u FAILED at %u", hunk_count, hunk_offset_start); |
207 | bad_hunk_count++; |
208 | break; |
209 | } |
210 | if (*patch_line != ' ') { /* '-' */ |
211 | continue; |
212 | } |
213 | } |
214 | if (dst_cur_line == dst_last_line) |
215 | break; |
216 | fputs(patch_line + 1, dst_stream); |
217 | dst_cur_line++; |
218 | } /* end of while loop handling one hunk */ |
219 | } /* end of while loop handling one file */ |
220 | |
221 | /* Cleanup last patched file */ |
222 | if (copy_trailing_lines_flag) { |
223 | copy_lines(src_stream, dst_stream, (unsigned)(-1)); |
224 | } |
225 | if (src_stream) { |
226 | fclose(src_stream); |
227 | } |
228 | fclose(dst_stream); |
229 | if (bad_hunk_count) { |
230 | ret = 1; |
231 | bb_error_msg("%u out of %u hunk FAILED", bad_hunk_count, hunk_count); |
232 | } else { |
233 | /* It worked, we can remove the backup */ |
234 | if (backup_filename) { |
235 | unlink(backup_filename); |
236 | } |
237 | if ((dst_cur_line == 0) || (dst_beg_line == 0)) { |
238 | /* The new patched file is empty, remove it */ |
239 | xunlink(new_filename); |
240 | // /* old_filename and new_filename may be the same file */ |
241 | // unlink(old_filename); |
242 | } |
243 | } |
244 | free(backup_filename); |
245 | //free(old_filename); |
246 | free(new_filename); |
247 | } /* end of "while there are patch lines" */ |
248 | quit: |
249 | /* 0 = SUCCESS |
250 | * 1 = Some hunks failed |
251 | * 2 = More serious problems (exited earlier) |
252 | */ |
253 | return ret; |
254 | } |