dd: code shrink
[oweals/busybox.git] / util-linux / hexdump.c
index 3798ce5d260d3146eb695b0942ddcc0580b877e5..ac7e24ff88022048d5a30aebfea20b34549d75ea 100644 (file)
  * Based on code from util-linux v 2.11l
  *
  * Copyright (c) 1989
- *     The Regents of the University of California.  All rights reserved.
+ * The Regents of the University of California.  All rights reserved.
  *
- * Licensed under GPLv2 or later, see file License in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
-#include "busybox.h"
-#include <getopt.h>
+//usage:#define hexdump_trivial_usage
+//usage:       "[-bcCdefnosvx" IF_FEATURE_HEXDUMP_REVERSE("R") "] [FILE]..."
+//usage:#define hexdump_full_usage "\n\n"
+//usage:       "Display FILEs (or stdin) in a user specified format\n"
+//usage:     "\n       -b              One-byte octal display"
+//usage:     "\n       -c              One-byte character display"
+//usage:     "\n       -C              Canonical hex+ASCII, 16 bytes per line"
+//usage:     "\n       -d              Two-byte decimal display"
+//usage:     "\n       -e FORMAT_STRING"
+//usage:     "\n       -f FORMAT_FILE"
+//usage:     "\n       -n LENGTH       Interpret only LENGTH bytes of input"
+//usage:     "\n       -o              Two-byte octal display"
+//usage:     "\n       -s OFFSET       Skip OFFSET bytes"
+//usage:     "\n       -v              Display all input data"
+//usage:     "\n       -x              Two-byte hexadecimal display"
+//usage:       IF_FEATURE_HEXDUMP_REVERSE(
+//usage:     "\n       -R              Reverse of 'hexdump -Cv'")
+//usage:
+//usage:#define hd_trivial_usage
+//usage:       "FILE..."
+//usage:#define hd_full_usage "\n\n"
+//usage:       "hd is an alias for hexdump -C"
+
+#include "libbb.h"
 #include "dump.h"
 
-static void bb_dump_addfile(char *name)
+/* This is a NOEXEC applet. Be very careful! */
+
+static void bb_dump_addfile(dumper_t *dumper, char *name)
 {
        char *p;
        FILE *fp;
        char *buf;
 
-       fp = xfopen(name, "r");
-
-       while ((buf = bb_get_chomped_line_from_file(fp)) != NULL) {
+       fp = xfopen_for_read(name);
+       while ((buf = xmalloc_fgetline(fp)) != NULL) {
                p = skip_whitespace(buf);
-
                if (*p && (*p != '#')) {
-                       bb_dump_add(p);
+                       bb_dump_add(dumper, p);
                }
                free(buf);
        }
        fclose(fp);
 }
 
-static const char * const add_strings[] = {
-       "\"%07.7_ax \" 16/1 \"%03o \" \"\\n\"",         /* b */
-       "\"%07.7_ax \" 16/1 \"%3_c \" \"\\n\"",         /* c */
-       "\"%07.7_ax \" 8/2 \"  %05u \" \"\\n\"",        /* d */
-       "\"%07.7_ax \" 8/2 \" %06o \" \"\\n\"",         /* o */
-       "\"%07.7_ax \" 8/2 \"   %04x \" \"\\n\"",       /* x */
+static const char *const add_strings[] = {
+       "\"%07.7_ax \" 16/1 \"%03o \" \"\\n\"",   /* b */
+       "\"%07.7_ax \" 16/1 \"%3_c \" \"\\n\"",   /* c */
+       "\"%07.7_ax \" 8/2 \"  %05u \" \"\\n\"",  /* d */
+       "\"%07.7_ax \" 8/2 \" %06o \" \"\\n\"",   /* o */
+       "\"%07.7_ax \" 8/2 \"   %04x \" \"\\n\"", /* x */
 };
 
-static const char add_first[] = "\"%07.7_Ax\n\"";
-
-static const char hexdump_opts[] = "bcdoxCe:f:n:s:v";
+static const char add_first[] ALIGN1 = "\"%07.7_Ax\n\"";
 
-static const struct suffix_mult suffixes[] = {
-       {"b",  512 },
-       {"k",  1024 },
-       {"m",  1024*1024 },
-       {NULL, 0 }
-};
+static const char hexdump_opts[] ALIGN1 = "bcdoxCe:f:n:s:v" IF_FEATURE_HEXDUMP_REVERSE("R");
 
+int hexdump_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int hexdump_main(int argc, char **argv)
 {
+       dumper_t *dumper = alloc_dumper();
        const char *p;
        int ch;
+#if ENABLE_FEATURE_HEXDUMP_REVERSE
+       FILE *fp;
+       smallint rdump = 0;
+#endif
 
-       bb_dump_vflag = FIRST;
-       bb_dump_length = -1;
+       if (ENABLE_HD && !applet_name[2]) { /* we are "hd" */
+               ch = 'C';
+               goto hd_applet;
+       }
 
+       /* We cannot use getopt32: in hexdump options are cumulative.
+        * E.g. "hexdump -C -C file" should dump each line twice */
        while ((ch = getopt(argc, argv, hexdump_opts)) > 0) {
-               p = strchr(hexdump_opts, ch)
+               p = strchr(hexdump_opts, ch);
                if (!p)
                        bb_show_usage();
                if ((p - hexdump_opts) < 5) {
-                       bb_dump_add(add_first);
-                       bb_dump_add(add_strings[(int)(p - hexdump_opts)]);
-               } else if (ch == 'C') {
-                       bb_dump_add("\"%08.8_Ax\n\"");
-                       bb_dump_add("\"%08.8_ax  \" 8/1 \"%02x \" \"  \" 8/1 \"%02x \" ");
-                       bb_dump_add("\"  |\" 16/1 \"%_p\" \"|\\n\"");
-               } else {
-                       /* Save a little bit of space below by omitting the 'else's. */
-                       if (ch == 'e') {
-                               bb_dump_add(optarg);
-                       } /* else */
-                       if (ch == 'f') {
-                               bb_dump_addfile(optarg);
-                       } /* else */
-                       if (ch == 'n') {
-                               bb_dump_length = bb_xgetularg10_bnd(optarg, 0, INT_MAX);
-                       } /* else */
-                       if (ch == 's') {
-                               bb_dump_skip = bb_xgetularg_bnd_sfx(optarg, 10, 0, LONG_MAX, suffixes);
-                       } /* else */
-                       if (ch == 'v') {
-                               bb_dump_vflag = ALL;
-                       }
+                       bb_dump_add(dumper, add_first);
+                       bb_dump_add(dumper, add_strings[(int)(p - hexdump_opts)]);
+               }
+               /* Save a little bit of space below by omitting the 'else's. */
+               if (ch == 'C') {
+ hd_applet:
+                       bb_dump_add(dumper, "\"%08.8_Ax\n\"");
+                       bb_dump_add(dumper, "\"%08.8_ax  \" 8/1 \"%02x \" \"  \" 8/1 \"%02x \" ");
+                       bb_dump_add(dumper, "\"  |\" 16/1 \"%_p\" \"|\\n\"");
                }
+               if (ch == 'e') {
+                       bb_dump_add(dumper, optarg);
+               } /* else */
+               if (ch == 'f') {
+                       bb_dump_addfile(dumper, optarg);
+               } /* else */
+               if (ch == 'n') {
+                       dumper->dump_length = xatoi_positive(optarg);
+               } /* else */
+               if (ch == 's') { /* compat: -s accepts hex numbers too */
+                       dumper->dump_skip = xstrtoull_range_sfx(
+                               optarg,
+                               /*base:*/ 0,
+                               /*lo:*/ 0, /*hi:*/ OFF_T_MAX,
+                               bkm_suffixes
+                       );
+               } /* else */
+               if (ch == 'v') {
+                       dumper->dump_vflag = ALL;
+               }
+#if ENABLE_FEATURE_HEXDUMP_REVERSE
+               if (ch == 'R') {
+                       rdump = 1;
+               }
+#endif
        }
 
-       if (!bb_dump_fshead) {
-               bb_dump_add(add_first);
-               bb_dump_add("\"%07.7_ax \" 8/2 \"%04x \" \"\\n\"");
+       if (!dumper->fshead) {
+               bb_dump_add(dumper, add_first);
+               bb_dump_add(dumper, "\"%07.7_ax \" 8/2 \"%04x \" \"\\n\"");
        }
 
        argv += optind;
 
-       return bb_dump_dump(argv);
+#if !ENABLE_FEATURE_HEXDUMP_REVERSE
+       return bb_dump_dump(dumper, argv);
+#else
+       if (!rdump) {
+               return bb_dump_dump(dumper, argv);
+       }
+
+       /* -R: reverse of 'hexdump -Cv' */
+       fp = stdin;
+       if (!*argv) {
+               argv--;
+               goto jump_in;
+       }
+
+       do {
+               char *buf;
+               fp = xfopen_for_read(*argv);
+ jump_in:
+               while ((buf = xmalloc_fgetline(fp)) != NULL) {
+                       p = buf;
+                       while (1) {
+                               /* skip address or previous byte */
+                               while (isxdigit(*p)) p++;
+                               while (*p == ' ') p++;
+                               /* '|' char will break the line */
+                               if (!isxdigit(*p) || sscanf(p, "%x ", &ch) != 1)
+                                       break;
+                               putchar(ch);
+                       }
+                       free(buf);
+               }
+               fclose(fp);
+       } while (*++argv);
+
+       fflush_stdout_and_exit(EXIT_SUCCESS);
+#endif
 }