/* vi: set sw=4 ts=4: */ /* * busybox patch applet to handle the unified diff format. * Copyright (C) 2003 Glenn McGrath * * Licensed under GPLv2 or later, see file LICENSE in this source tree. * * 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 "libbb.h" static unsigned copy_lines(FILE *src_stream, FILE *dst_stream, unsigned lines_count) { while (src_stream && lines_count) { char *line; line = xmalloc_fgets(src_stream); if (line == NULL) { break; } if (fputs(line, dst_stream) == EOF) { bb_perror_msg_and_die("error writing to new file"); } free(line); lines_count--; } return lines_count; } /* 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 * NB: frees 1st argument! */ static char *extract_filename(char *line, int patch_level, const char *pat) { char *temp = NULL, *filename_start_ptr = line + 4; if (strncmp(line, pat, 4) == 0) { /* Terminate string at end of source filename */ line[strcspn(line, "\t\n\r")] = '\0'; /* Skip over (patch_level) number of leading directories */ while (patch_level--) { temp = strchr(filename_start_ptr, '/'); if (!temp) break; filename_start_ptr = temp + 1; } temp = xstrdup(filename_start_ptr); } free(line); return temp; } int patch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int patch_main(int argc UNUSED_PARAM, char **argv) { struct stat saved_stat; char *patch_line; FILE *patch_file; int patch_level; int ret = 0; char plus = '+'; unsigned opt; enum { OPT_R = (1 << 2), OPT_N = (1 << 3), /*OPT_f = (1 << 4), ignored */ /*OPT_E = (1 << 5), ignored, this is the default */ /*OPT_g = (1 << 6), ignored */ OPT_dry_run = (1 << 7) * ENABLE_LONG_OPTS, }; xfunc_error_retval = 2; { const char *p = "-1"; const char *i = "-"; /* compat */ #if ENABLE_LONG_OPTS static const char patch_longopts[] ALIGN1 = "strip\0" Required_argument "p" "input\0" Required_argument "i" "reverse\0" No_argument "R" "forward\0" No_argument "N" /* "Assume user knows what [s]he is doing, do not ask any questions": */ "force\0" No_argument "f" /*ignored*/ # if ENABLE_DESKTOP "remove-empty-files\0" No_argument "E" /*ignored*/ /* "Controls actions when a file is under RCS or SCCS control, * and does not exist or is read-only and matches the default version, * or when a file is under ClearCase control and does not exist..." * IOW: rather obscure option. * But Gentoo's portage does use -g0 */ "get\0" Required_argument "g" /*ignored*/ # endif "dry-run\0" No_argument "\xfd" # if ENABLE_DESKTOP "backup-if-mismatch\0" No_argument "\xfe" /*ignored*/ "no-backup-if-mismatch\0" No_argument "\xff" /*ignored*/ # endif ; applet_long_options = patch_longopts; #endif /* -f,-E,-g are ignored */ opt = getopt32(argv, "p:i:RN""fEg:", &p, &i, NULL); if (opt & OPT_R) plus = '-'; patch_level = xatoi(p); /* can be negative! */ patch_file = xfopen_stdin(i); } patch_line = xmalloc_fgetline(patch_file); while (patch_line) { FILE *src_stream; FILE *dst_stream; //char *old_filename; char *new_filename; char *backup_filename = NULL; unsigned src_cur_line = 1; unsigned dst_cur_line = 0; unsigned dst_beg_line; unsigned bad_hunk_count = 0; unsigned hunk_count = 0; smallint copy_trailing_lines_flag = 0; /* Skip everything upto the "---" marker * No need to parse the lines "Only in <dir>", and "diff <args>" */ do { /* Extract the filename used before the patch was generated */ new_filename = extract_filename(patch_line, patch_level, "--- "); // was old_filename above patch_line = xmalloc_fgetline(patch_file); if (!patch_line) goto quit; } while (!new_filename); free(new_filename); // "source" filename is irrelevant new_filename = extract_filename(patch_line, patch_level, "+++ "); if (!new_filename) { bb_error_msg_and_die("invalid patch"); } /* Get access rights from the file to be patched */ if (stat(new_filename, &saved_stat) != 0) { char *slash = strrchr(new_filename, '/'); if (slash) { /* Create leading directories */ *slash = '\0'; bb_make_directory(new_filename, -1, FILEUTILS_RECUR); *slash = '/'; } src_stream = NULL; saved_stat.st_mode = 0644; } else if (!(opt & OPT_dry_run)) { backup_filename = xasprintf("%s.orig", new_filename); xrename(new_filename, backup_filename); src_stream = xfopen_for_read(backup_filename); } else src_stream = xfopen_for_read(new_filename); if (opt & OPT_dry_run) { dst_stream = xfopen_for_write("/dev/null"); } else { dst_stream = xfopen_for_write(new_filename); fchmod(fileno(dst_stream), saved_stat.st_mode); } printf("patching file %s\n", new_filename); /* Handle all hunks for this file */ patch_line = xmalloc_fgets(patch_file); while (patch_line) { unsigned count; unsigned src_beg_line; unsigned hunk_offset_start; unsigned src_last_line = 1; unsigned dst_last_line = 1; if ((sscanf(patch_line, "@@ -%d,%d +%d,%d", &src_beg_line, &src_last_line, &dst_beg_line, &dst_last_line) < 3) && (sscanf(patch_line, "@@ -%d +%d,%d", &src_beg_line, &dst_beg_line, &dst_last_line) < 2) ) { /* No more hunks for this file */ break; } if (plus != '+') { /* reverse patch */ unsigned tmp = src_last_line; src_last_line = dst_last_line; dst_last_line = tmp; tmp = src_beg_line; src_beg_line = dst_beg_line; dst_beg_line = tmp; } hunk_count++; if (src_beg_line && dst_beg_line) { /* Copy unmodified lines upto start of hunk */ /* src_beg_line will be 0 if it's a new file */ count = src_beg_line - src_cur_line; if (copy_lines(src_stream, dst_stream, count)) { bb_error_msg_and_die("bad src file"); } src_cur_line += count; dst_cur_line += count; copy_trailing_lines_flag = 1; } src_last_line += hunk_offset_start = src_cur_line; dst_last_line += dst_cur_line; while (1) { free(patch_line); patch_line = xmalloc_fgets(patch_file); if (patch_line == NULL) break; /* EOF */ if (!*patch_line) { /* whitespace-damaged patch with "" lines */ free(patch_line); patch_line = xstrdup(" "); } if ((*patch_line != '-') && (*patch_line != '+') && (*patch_line != ' ') ) { break; /* End of hunk */ } if (*patch_line != plus) { /* '-' or ' ' */ char *src_line = NULL; if (src_cur_line == src_last_line) break; if (src_stream) { src_line = xmalloc_fgets(src_stream); if (src_line) { int diff = strcmp(src_line, patch_line + 1); src_cur_line++; free(src_line); if (diff) src_line = NULL; } } /* Do not patch an already patched hunk with -N */ if (src_line == 0 && (opt & OPT_N)) { continue; } if (!src_line) { bb_error_msg("hunk #%u FAILED at %u", hunk_count, hunk_offset_start); bad_hunk_count++; break; } if (*patch_line != ' ') { /* '-' */ continue; } } if (dst_cur_line == dst_last_line) break; fputs(patch_line + 1, dst_stream); dst_cur_line++; } /* end of while loop handling one hunk */ } /* end of while loop handling one file */ /* Cleanup last patched file */ if (copy_trailing_lines_flag) { copy_lines(src_stream, dst_stream, (unsigned)(-1)); } if (src_stream) { fclose(src_stream); } fclose(dst_stream); if (bad_hunk_count) { ret = 1; bb_error_msg("%u out of %u hunk FAILED", bad_hunk_count, hunk_count); } else { /* It worked, we can remove the backup */ if (backup_filename) { unlink(backup_filename); } if (!(opt & OPT_dry_run) && ((dst_cur_line == 0) || (dst_beg_line == 0)) ) { /* The new patched file is empty, remove it */ xunlink(new_filename); // /* old_filename and new_filename may be the same file */ // unlink(old_filename); } } free(backup_filename); //free(old_filename); free(new_filename); } /* end of "while there are patch lines" */ quit: /* 0 = SUCCESS * 1 = Some hunks failed * 2 = More serious problems (exited earlier) */ return ret; }