New applet: patch, applies a unified diff
authorGlenn L McGrath <bug1@ihug.co.nz>
Sun, 22 Jun 2003 15:32:41 +0000 (15:32 -0000)
committerGlenn L McGrath <bug1@ihug.co.nz>
Sun, 22 Jun 2003 15:32:41 +0000 (15:32 -0000)
editors/Config.in
editors/Makefile.in
editors/patch.c [new file with mode: 0644]
include/applets.h
include/usage.h

index c752677594365ce6616b36e99aa2185417abbb1a..b7135f39325a35f3793c51df4fb92c3928ebd4c6 100644 (file)
@@ -18,6 +18,12 @@ config CONFIG_FEATURE_AWK_MATH
        help
          Please submit a patch to add help text for this item.
 
+config CONFIG_PATCH
+       bool "patch"
+       default n
+       help
+         Apply a unified diff formated patch.
+
 config CONFIG_SED
        bool "sed"
        default n
index f4f604e6a6a78765815654299efa86acdad1ab75..cf6006a2cb97140693a041e9fcb7bf6cdfe7011e 100644 (file)
@@ -24,6 +24,7 @@ endif
 
 EDITOR-y:=
 EDITOR-$(CONFIG_AWK)      += awk.o
+EDITOR-$(CONFIG_PATCH)    += patch.o
 EDITOR-$(CONFIG_SED)       += sed.o
 EDITOR-$(CONFIG_VI)        += vi.o
 EDITOR_SRC:= $(EDITOR-y)
diff --git a/editors/patch.c b/editors/patch.c
new file mode 100644 (file)
index 0000000..1587919
--- /dev/null
@@ -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);
+}
index 01cfb8629b9805814e03f5e2f11dbc797ca4896d..cfb278123cc042037e661a94c67e943207af36be 100644 (file)
 #ifdef CONFIG_PASSWD
        APPLET(passwd, passwd_main, _BB_DIR_USR_BIN, _BB_SUID_ALWAYS)
 #endif
+#ifdef CONFIG_PATCH
+       APPLET(patch, patch_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER)
+#endif
 #ifdef CONFIG_PIDFILEHACK
        APPLET(pidfilehack, pidfilehack_main, _BB_DIR_BIN, _BB_SUID_NEVER)
 #endif
index d60a4dc78a3de4f688e0361ccebddfc1228bd5e4..701b40daac2b27b6ec43c3f934e9fc3f02101571 100644 (file)
        "\t-l\tLocks (disables) the specified user account.\n" \
        "\t-u\tUnlocks (re-enables) the specified user account."
 
+#define patch_trivial_usage \
+       "[-p<num>]"
+#define patch_full_usage \
+       "[-p<num>]"
+#define patch_example_usage \
+       "$ patch -p1 <example.diff"
+
 #define pidfilehack_trivial_usage \
        "[daemon.pid] [daemon]"
 #define pidfilehack_full_usage \