UNIX 7th Ed. - /usr/src/cmd/du.c

   1: #include <stdio.h>
   2: #include <sys/param.h>
   3: #include <sys/stat.h>
   4: #include <sys/dir.h>
   5: #define EQ(x,y) (strcmp(x,y)==0)
   6: #define ML  1000
   7: 
   8: struct stat Statb;
   9: char    path[256], name[256];
  10: int Aflag = 0,
  11:     Sflag = 0,
  12:     Noarg = 0;
  13: struct {
  14:     int dev,
  15:         ino;
  16: } ml[ML];
  17: long    descend();
  18: char    *rindex();
  19: char    *strcpy();
  20: 
  21: main(argc, argv)
  22: char **argv;
  23: {
  24:     register    i = 1;
  25:     long    blocks = 0;
  26:     register char   *np;
  27: 
  28:     if (argc>1) {
  29:         if(EQ(argv[i], "-s")) {
  30:             ++i;
  31:             ++Sflag;
  32:         } else if(EQ(argv[i], "-a")) {
  33:             ++i;
  34:             ++Aflag;
  35:         }
  36:     }
  37:     if(i == argc)
  38:         ++Noarg;
  39: 
  40:     do {
  41:         strcpy(path, Noarg? ".": argv[i]);
  42:         strcpy(name, path);
  43:         if(np = rindex(name, '/')) {
  44:             *np++ = '\0';
  45:             if(chdir(*name? name: "/") == -1) {
  46:                 fprintf(stderr, "cannot chdir()\n");
  47:                 exit(1);
  48:             }
  49:         } else
  50:             np = path;
  51:         blocks = descend(path, *np? np: ".");
  52:         if(Sflag)
  53:             printf("%ld	%s\n", blocks, path);
  54:     } while(++i < argc);
  55: 
  56:     exit(0);
  57: }
  58: 
  59: long
  60: descend(np, fname)
  61: char *np, *fname;
  62: {
  63:     int dir = 0, /* open directory */
  64:         offset,
  65:         dsize,
  66:         entries,
  67:         dirsize;
  68: 
  69:     struct direct dentry[32];
  70:     register  struct direct *dp;
  71:     register char *c1, *c2;
  72:     int i;
  73:     char *endofname;
  74:     long blocks = 0;
  75: 
  76:     if(stat(fname,&Statb)<0) {
  77:         fprintf(stderr, "--bad status < %s >\n", name);
  78:         return 0L;
  79:     }
  80:     if(Statb.st_nlink > 1 && (Statb.st_mode&S_IFMT)!=S_IFDIR) {
  81:         static linked = 0;
  82: 
  83:         for(i = 0; i <= linked; ++i) {
  84:             if(ml[i].ino==Statb.st_ino && ml[i].dev==Statb.st_dev)
  85:                 return 0;
  86:         }
  87:         if (linked < ML) {
  88:             ml[linked].dev = Statb.st_dev;
  89:             ml[linked].ino = Statb.st_ino;
  90:             ++linked;
  91:         }
  92:     }
  93:     blocks = (Statb.st_size + BSIZE-1) >> BSHIFT;
  94: 
  95:     if((Statb.st_mode&S_IFMT)!=S_IFDIR) {
  96:         if(Aflag)
  97:             printf("%ld	%s\n", blocks, np);
  98:         return(blocks);
  99:     }
 100: 
 101:     for(c1 = np; *c1; ++c1);
 102:     if(*(c1-1) == '/')
 103:         --c1;
 104:     endofname = c1;
 105:     dirsize = Statb.st_size;
 106:     if(chdir(fname) == -1)
 107:         return 0;
 108:     for(offset=0; offset < dirsize; offset += 512) { /* each block */
 109:         dsize = 512<(dirsize-offset)? 512: (dirsize-offset);
 110:         if(!dir) {
 111:             if((dir=open(".",0))<0) {
 112:                 fprintf(stderr, "--cannot open < %s >\n",
 113:                     np);
 114:                 goto ret;
 115:             }
 116:             if(offset) lseek(dir, (long)offset, 0);
 117:             if(read(dir, (char *)dentry, dsize)<0) {
 118:                 fprintf(stderr, "--cannot read < %s >\n",
 119:                     np);
 120:                 goto ret;
 121:             }
 122:             if(dir > 10) {
 123:                 close(dir);
 124:                 dir = 0;
 125:             }
 126:         } else
 127:             if(read(dir, (char *)dentry, dsize)<0) {
 128:                 fprintf(stderr, "--cannot read < %s >\n",
 129:                     np);
 130:                 goto ret;
 131:             }
 132:         for(dp=dentry, entries=dsize>>4; entries; --entries, ++dp) {
 133:             /* each directory entry */
 134:             if(dp->d_ino==0
 135:             || EQ(dp->d_name, ".")
 136:             || EQ(dp->d_name, ".."))
 137:                 continue;
 138:             c1 = endofname;
 139:             *c1++ = '/';
 140:             c2 = dp->d_name;
 141:             for(i=0; i<DIRSIZ; ++i)
 142:                 if(*c2)
 143:                     *c1++ = *c2++;
 144:                 else
 145:                     break;
 146:             *c1 = '\0';
 147:             if(c1 == endofname) /* ?? */
 148:                 return 0L;
 149:             blocks += descend(np, endofname+1);
 150:         }
 151:     }
 152:     *endofname = '\0';
 153:     if(!Sflag)
 154:         printf("%ld	%s\n", blocks, np);
 155: ret:
 156:     if(dir)
 157:         close(dir);
 158:     if(chdir("..") == -1) {
 159:         *endofname = '\0';
 160:         fprintf(stderr, "Bad directory <%s>\n", np);
 161:         while(*--endofname != '/');
 162:         *endofname = '\0';
 163:         if(chdir(np) == -1)
 164:             exit(1);
 165:     }
 166:     return(blocks);
 167: }

Defined functions

Defined variables

Defined macros