usr/src/lib/libcmd/common/cmp.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1992-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                                                                      *
  20 ***********************************************************************/
  21 #pragma prototyped
  22 /*
  23  * David Korn
  24  * Glenn Fowler
  25  * AT&T Bell Laboratories
  26  *
  27  * cmp
  28  */
  29
  30 static const char usage[] =
  31 "[-?\n@(#)$Id: cmp (AT&T Research) 2009-01-05 $\n]"
  32 USAGE_LICENSE
  33 "[+NAME?cmp - compare two files]"
  34 "[+DESCRIPTION?\bcmp\b compares two files \afile1\a and \afile2\a.  "
  35         "\bcmp\b writes no output if the files are the same.  By default, "
  36         "if the files differ, the byte and line number at which the "
  37         "first difference occurred are written to standard output.  Bytes "
  38         "and lines are numbered beginning with 1.]"
  39 "[+?If \askip1\a or \askip2\a are specified, or the \b-i\b option is "
  40         "specified, initial bytes of the corresponding file are skipped "
  41         "before beginning the compare.  The skip values are in bytes or "
  42         "can have a suffix of \bk\b for kilobytes or \bm\b for megabytes.]"
  43 "[+?If either \afile1\a or \afiles2\a is \b-\b, \bcmp\b "
  44         "uses standard input starting at the current location.]"
  45 "[c:print-chars?Writes control characters as a \b^\b followed by a letter of "
  46         "the alphabet and precede characters that have the high bit set with "
  47         "\bM-\b as with \bcat\b(1).]"
  48 "[i:ignore-initial]#[skip:=0?Sets default skip values for the operands "
  49         "\askip1\a and \askip2\a to \askip\a.]"
  50 "[l:verbose?Write the decimal byte number and the differing bytes (in octal) "
  51         "for each difference.]"
  52 "[s:quiet|silent?Write nothing for differing files; return non-zero "
  53         "exit status only.] ]"
  54 "\n"
  55 "\nfile1 file2 [skip1 [skip2]]\n"
  56 "\n"
  57 "[+EXIT STATUS?]{"
  58         "[+0?The files or portions compared are identical.]"
  59         "[+1?The files are different.]"
  60         "[+>1?An error occurred.]"
  61 "}"
  62 "[+SEE ALSO?\bcomm\b(1), \bdiff\b(1), \bcat\b(1)]"
  63 ;
  64
  65
  66 #include <cmd.h>
  67 #include <ls.h>
  68 #include <ctype.h>
  69
  70 #define CMP_VERBOSE     1
  71 #define CMP_SILENT      2
  72 #define CMP_CHARS       4
  73
  74 #define cntl(x)         (x&037)
  75 #define printchar(c)    ((c) ^ ('A'-cntl('A')))
  76
  77 static void outchar(Sfio_t *out, register int c, int delim)
  78 {
  79         if(c&0200)
  80         {
  81                 sfputc(out,'M');
  82                 sfputc(out,'-');
  83                 c &= ~0200;
  84         }
  85         else if(!isprint(c))
  86         {
  87                 sfputc(out,'^');
  88                 c = printchar(c);
  89         }
  90         sfputc(out,c);
  91         sfputc(out,delim);
  92 }
  93
  94 /*
  95  * compare two files
  96  */
  97
  98 static int
  99 cmp(const char* file1, Sfio_t* f1, const char* file2, Sfio_t* f2, int flags)
 100 {
 101         register int            c1;
 102         register int            c2;
 103         register unsigned char* p1 = 0;
 104         register unsigned char* p2 = 0;
 105         register Sfoff_t        lines = 1;
 106         register unsigned char* e1 = 0;
 107         register unsigned char* e2 = 0;
 108         Sfoff_t                 pos = 0;
 109         int                     ret = 0;
 110         unsigned char*          last;
 111
 112         for (;;)
 113         {
 114                 if ((c1 = e1 - p1) <= 0)
 115                 {
 116                         if (!(p1 = (unsigned char*)sfreserve(f1, SF_UNBOUND, 0)) || (c1 = sfvalue(f1)) <= 0)
 117                         {
 118                                 if ((e2 - p2) > 0 || sfreserve(f2, SF_UNBOUND, 0) && sfvalue(f2) > 0)
 119                                 {
 120                                         ret = 1;
 121                                         if (!(flags & CMP_SILENT))
 122                                                 error(ERROR_exit(1), "EOF on %s", file1);
 123                                 }
 124                                 return(ret);
 125                         }
 126                         e1 = p1 + c1;
 127                 }
 128                 if ((c2 = e2 - p2) <= 0)
 129                 {
 130                         if (!(p2 = (unsigned char*)sfreserve(f2, SF_UNBOUND, 0)) || (c2 = sfvalue(f2)) <= 0)
 131                         {
 132                                 if (!(flags & CMP_SILENT))
 133                                         error(ERROR_exit(1), "EOF on %s", file2);
 134                                 return(1);
 135                         }
 136                         e2 = p2 + c2;
 137                 }
 138                 if (c1 > c2)
 139                         c1 = c2;
 140                 pos += c1;
 141                 if (flags & CMP_SILENT)
 142                 {
 143                         if (memcmp(p1, p2, c1))
 144                                 return(1);
 145                         p1 += c1;
 146                         p2 += c1;
 147                 }
 148                 else
 149                 {
 150                         last = p1 + c1;
 151                         while (p1 < last)
 152                         {
 153                                 if ((c1 = *p1++) != *p2++)
 154                                 {
 155                                         if (flags)
 156                                         {
 157                                                 ret = 1;
 158                                                 if(flags&CMP_CHARS)
 159                                                 {
 160                                                         sfprintf(sfstdout, "%6I*d ", sizeof(pos), pos - (last - p1));
 161                                                         outchar(sfstdout,c1,' ');
 162                                                         outchar(sfstdout,*(p2-1),'\n');
 163                                                 }
 164                                                 else
 165                                                         sfprintf(sfstdout, "%6I*d %3o %3o\n", sizeof(pos), pos - (last - p1), c1, *(p2 - 1));
 166                                         }
 167                                         else
 168                                         {
 169                                                 sfprintf(sfstdout, "%s %s differ: char %I*d, line %I*u\n", file1, file2, sizeof(pos), pos - (last - p1), sizeof(lines), lines);
 170                                                 return(1);
 171                                         }
 172                                 }
 173                                 if (c1 == '\n')
 174                                         lines++;
 175                         }
 176                 }
 177         }
 178 }
 179
 180 int
 181 b_cmp(int argc, register char** argv, void* context)
 182 {
 183         char*           s;
 184         char*           e;
 185         Sfio_t*         f1 = 0;
 186         Sfio_t*         f2 = 0;
 187         char*           file1;
 188         char*           file2;
 189         int             n;
 190         off_t           o1 = 0;
 191         off_t           o2 = 0;
 192         struct stat     s1;
 193         struct stat     s2;
 194
 195         int             flags = 0;
 196
 197         NoP(argc);
 198         cmdinit(argc, argv, context, ERROR_CATALOG, 0);
 199         while (n = optget(argv, usage)) switch (n)
 200         {
 201         case 'l':
 202                 flags |= CMP_VERBOSE;
 203                 break;
 204         case 's':
 205                 flags |= CMP_SILENT;
 206                 break;
 207         case 'c':
 208                 flags |= CMP_CHARS;
 209                 break;
 210         case 'i':
 211                 o1 = o2 = opt_info.num;
 212                 break;
 213         case ':':
 214                 error(2, "%s", opt_info.arg);
 215                 break;
 216         case '?':
 217                 error(ERROR_usage(2), "%s", opt_info.arg);
 218                 break;
 219         }
 220         argv += opt_info.index;
 221         if (error_info.errors || !(file1 = *argv++) || !(file2 = *argv++))
 222                 error(ERROR_usage(2), "%s", optusage(NiL));
 223         n = 2;
 224         if (streq(file1, "-"))
 225                 f1 = sfstdin;
 226         else if (!(f1 = sfopen(NiL, file1, "r")))
 227         {
 228                 if (!(flags & CMP_SILENT))
 229                         error(ERROR_system(0), "%s: cannot open", file1);
 230                 goto done;
 231         }
 232         if (streq(file2, "-"))
 233                 f2 = sfstdin;
 234         else if (!(f2 = sfopen(NiL, file2, "r")))
 235         {
 236                 if (!(flags & CMP_SILENT))
 237                         error(ERROR_system(0), "%s: cannot open", file2);
 238                 goto done;
 239         }
 240         if (s = *argv++)
 241         {
 242                 o1 = strtol(s, &e, 0);
 243                 if (*e)
 244                 {
 245                         error(ERROR_exit(0), "%s: %s: invalid skip", file1, s);
 246                         goto done;
 247                 }
 248                 if (s = *argv++)
 249                 {
 250                         o2 = strtol(s, &e, 0);
 251                         if (*e)
 252                         {
 253                                 error(ERROR_exit(0), "%s: %s: invalid skip", file2, s);
 254                                 goto done;
 255                         }
 256                 }
 257                 if (*argv)
 258                 {
 259                         error(ERROR_usage(0), "%s", optusage(NiL));
 260                         goto done;
 261                 }
 262         }
 263         if (o1 && sfseek(f1, o1, SEEK_SET) != o1)
 264         {
 265                 if (!(flags & CMP_SILENT))
 266                         error(ERROR_exit(0), "EOF on %s", file1);
 267                 n = 1;
 268                 goto done;
 269         }
 270         if (o2 && sfseek(f2, o2, SEEK_SET) != o2)
 271         {
 272                 if (!(flags & CMP_SILENT))
 273                         error(ERROR_exit(0), "EOF on %s", file2);
 274                 n = 1;
 275                 goto done;
 276         }
 277         if (fstat(sffileno(f1), &s1))
 278                 error(ERROR_system(0), "%s: cannot stat", file1);
 279         else if (fstat(sffileno(f2), &s2))
 280                 error(ERROR_system(0), "%s: cannot stat", file1);
 281         else if (s1.st_ino == s2.st_ino && s1.st_dev == s2.st_dev && o1 == o2)
 282                 n = 0;
 283         else
 284                 n = ((flags & CMP_SILENT) && S_ISREG(s1.st_mode) && S_ISREG(s2.st_mode) && (s1.st_size - o1) != (s2.st_size - o2)) ? 1 : cmp(file1, f1, file2, f2, flags);
 285  done:
 286         if (f1 && f1 != sfstdin) sfclose(f1);
 287         if (f2 && f2 != sfstdin) sfclose(f2);
 288         return(n);
 289 }