1 /* split.c - split a file into smaller files 2 * 3 * Copyright 2013 Rob Landley <rob (at) landley.net> 4 * 5 * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/split.html 6 * 7 * Standard does not cover: 8 * - should splitting an empty file produce an empty outfile? (Went with "no".) 9 * - permissions on output file 10 11 USE_SPLIT(NEWTOY(split, ">2a#<1=2>9b#<1l#<1[!bl]", TOYFLAG_USR|TOYFLAG_BIN)) 12 13 config SPLIT 14 bool "split" 15 default y 16 help 17 usage: split [-a SUFFIX_LEN] [-b BYTES] [-l LINES] [INPUT [OUTPUT]] 18 19 Copy INPUT (or stdin) data to a series of OUTPUT (or "x") files with 20 alphabetically increasing suffix (aa, ab, ac... az, ba, bb...). 21 22 -a Suffix length (default 2) 23 -b BYTES/file (10, 10k, 10m, 10g...) 24 -l LINES/file (default 1000) 25 */ 26 27 #define FOR_split 28 #include "toys.h" 29 30 GLOBALS( 31 long l, b, a; 32 33 char *outfile; 34 ) 35 36 static void do_split(int infd, char *in) 37 { 38 unsigned long bytesleft, linesleft, filenum, len, pos; 39 int outfd = -1; 40 struct stat st; 41 42 // posix doesn't cover permissions on output file, so copy input (or 0777) 43 st.st_mode = 0777; 44 fstat(infd, &st); 45 46 len = pos = filenum = bytesleft = linesleft = 0; 47 for (;;) { 48 int i, j; 49 50 // Refill toybuf? 51 if (len == pos) { 52 if (!(len = xread(infd, toybuf, sizeof(toybuf)))) break; 53 pos = 0; 54 } 55 56 // Start new output file? 57 if ((TT.b && !bytesleft) || (TT.l && !linesleft)) { 58 char *s = TT.outfile + strlen(TT.outfile); 59 60 j = filenum++; 61 for (i = 0; i<TT.a; i++) { 62 *(--s) = 'a'+(j%26); 63 j /= 26; 64 } 65 if (j) error_exit("bad suffix"); 66 bytesleft = TT.b; 67 linesleft = TT.l; 68 if (outfd != -1) close(outfd); 69 outfd = xcreate(TT.outfile, O_RDWR|O_CREAT|O_TRUNC, st.st_mode & 0777); 70 } 71 72 // Write next chunk of output. 73 if (TT.l) { 74 for (i = pos; i < len; ) { 75 if (toybuf[i++] == '\n' && !--linesleft) break; 76 if (!--bytesleft) break; 77 } 78 j = i - pos; 79 } else { 80 j = len - pos; 81 if (j > bytesleft) j = bytesleft; 82 bytesleft -= j; 83 } 84 xwrite(outfd, toybuf+pos, j); 85 pos += j; 86 } 87 88 if (CFG_TOYBOX_FREE) { 89 if (outfd != -1) close(outfd); 90 if (infd) close(infd); 91 free(TT.outfile); 92 } 93 xexit(); 94 } 95 96 void split_main(void) 97 { 98 if (!TT.b && !TT.l) TT.l = 1000; 99 100 // Allocate template for output filenames 101 TT.outfile = xmprintf("%s%*c", (toys.optc == 2) ? toys.optargs[1] : "x", 102 (int)TT.a, ' '); 103 104 // We only ever use one input, but this handles '-' or no input for us. 105 loopfiles(toys.optargs, do_split); 106 } 107