New applet: patch, applies a unified diff
diff --git a/editors/patch.c b/editors/patch.c
new file mode 100644
index 0000000..1587919
--- /dev/null
+++ b/editors/patch.c
@@ -0,0 +1,290 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * busybox patch applet to handle the unified diff format.
+ * Copyright (C) 2003 Glenn McGrath <bug1@optushome.com.au>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ *
+ *
+ * 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 the hunk will fail.
+ * - Reject file isnt saved
+ * -
+ */
+
+#include <getopt.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include "busybox.h"
+#include "libbb.h"
+
+static int copy_lines(FILE *src_stream, FILE *dest_stream, const unsigned int lines_count)
+{
+ int i = 0;
+
+ while (src_stream && (i < lines_count)) {
+ char *line;
+ line = bb_get_line_from_file(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 unsigned char *extract_filename(char *line, unsigned short patch_level)
+{
+ char *filename_start_ptr = line + 4;
+ int i;
+
+ /* Terminate string at end of source filename */
+ {
+ char *line_ptr;
+ line_ptr = strchr(filename_start_ptr, '\t');
+ if (!line_ptr) {
+ bb_perror_msg("Malformed line %s", line);
+ return(NULL);
+ }
+ *line_ptr = '\0';
+ }
+
+ /* Skip over (patch_level) number of leading directories */
+ for (i = 0; i < patch_level; i++) {
+ char *dirname_ptr;
+
+ dirname_ptr = strchr(filename_start_ptr, '/');
+ if (!dirname_ptr) {
+ break;
+ }
+ filename_start_ptr = dirname_ptr + 1;
+ }
+
+ return(bb_xstrdup(filename_start_ptr));
+}
+
+static int file_doesnt_exist(const char *filename)
+{
+ struct stat statbuf;
+ return(stat(filename, &statbuf));
+}
+
+extern int patch_main(int argc, char **argv)
+{
+ unsigned int patch_level = -1;
+ char *patch_line;
+ int ret = 0;
+
+ /* Handle 'p' option */
+ if (argv[1] && (argv[1][0] == '-') && (argv[1][1] == 'p')) {
+ patch_level = atoi(&argv[1][2]);
+ }
+
+ patch_line = bb_get_line_from_file(stdin);
+ 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 = bb_get_line_from_file(stdin);
+ }
+
+ /* Extract the filename used before the patch was generated */
+ original_filename = extract_filename(patch_line, patch_level);
+ free(patch_line);
+
+ patch_line = bb_get_line_from_file(stdin);
+ 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 = bb_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("Couldnt create file %s", backup_filename);
+ }
+ dst_stream = bb_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 = bb_xfopen(backup_filename, "r");
+ } else {
+ src_stream = bb_xfopen(original_filename, "r");
+ }
+ }
+
+ printf("patching file %s\n", new_filename);
+
+ /* Handle each hunk */
+ patch_line = bb_get_line_from_file(stdin);
+ 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 = bb_get_line_from_file(stdin)) != NULL) {
+ if ((*patch_line == '-') || (*patch_line == ' ')) {
+ char *src_line = NULL;
+ if (src_stream) {
+ src_line = bb_get_line_from_file(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);
+ 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("Couldnt remove file %s", new_filename);
+ }
+ if (unlink(original_filename) == -1) {
+ bb_perror_msg_and_die("Couldnt remove original file %s", new_filename);
+ }
+ }
+ }
+ }
+
+ /* 0 = SUCCESS
+ * 1 = Some hunks failed
+ * 2 = More serious problems
+ */
+ return(ret);
+}