Add od -w.

I'm not an od user myself, but I copy & pasted an 'od' invocation from a bug
and it didn't work. Which was embarrassing because I'd just claimed that the
od user didn't need to run od on their desktop (as they had done) and could
have run it on the device instead...

1 files changed, 21 insertions, 13 deletions

diff --git a/toys/posix/od.c b/toys/posix/od.c
index 99219bf4..5ccea58c 100644
--- a/toys/posix/od.c
+++ b/toys/posix/od.c
@@ -5,21 +5,22 @@
  *
  * See http://opengroup.org/onlinepubs/9699919799/utilities/od.html
 
-USE_OD(NEWTOY(od, "j#vN#xsodcbA:t*", TOYFLAG_USR|TOYFLAG_BIN))
+USE_OD(NEWTOY(od, "j#vw#<1=16N#xsodcbA:t*", TOYFLAG_USR|TOYFLAG_BIN))
 
 config OD
   bool "od"
   default y
   help
-    usage: od [-bcdosxv] [-j #] [-N #] [-A doxn] [-t acdfoux[#]]
+    usage: od [-bcdosxv] [-j #] [-N #] [-w #] [-A doxn] [-t acdfoux[#]]
 
     -A	Address base (decimal, octal, hexdecimal, none)
     -j	Skip this many bytes of input
     -N	Stop dumping after this many bytes
-    -t	output type a(scii) c(har) d(ecimal) f(loat) o(ctal) u(nsigned) (he)x
+    -t	Output type a(scii) c(har) d(ecimal) f(loat) o(ctal) u(nsigned) (he)x
     	plus optional size in bytes
     	aliases: -b=-t o1, -c=-t c, -d=-t u2, -o=-t o2, -s=-t d2, -x=-t x2
     -v	Don't collapse repeated lines together
+    -w	Total line width in bytes (default 16).
 */
 
 #define FOR_od
@@ -29,12 +30,13 @@ GLOBALS(
   struct arg_list *output_base;
   char *address_base;
   long max_count;
+  long width;
   long jump_bytes;
 
   int address_idx;
   unsigned types, leftover, star;
-  char *buf;
-  uint64_t bufs[4]; // force 64-bit alignment
+  char *buf; // Points to buffers[0] or buffers[1].
+  char *bufs[2]; // Used to detect duplicate lines.
   off_t pos;
 )
 
@@ -129,11 +131,11 @@ static void od_outline(void)
   struct odtype *types = (struct odtype *)toybuf;
   int i, j, len, pad;
 
-  if (TT.leftover<16) memset(TT.buf+TT.leftover, 0, 16-TT.leftover);
+  if (TT.leftover<TT.width) memset(TT.buf+TT.leftover, 0, TT.width-TT.leftover);
 
   // Handle duplciate lines as *
   if (!(flags&FLAG_v) && TT.jump_bytes != TT.pos && TT.leftover
-    && !memcmp(TT.bufs, TT.bufs + 2, 16))
+    && !memcmp(TT.bufs[0], TT.bufs[1], TT.width))
   {
     if (!TT.star) {
       xputs("*");
@@ -168,7 +170,6 @@ static void od_outline(void)
   }
 
   // For each output type, print one line
-
   for (i=0; i<TT.types; i++) {
     for (j = 0; j<len;) {
       int bytes = j;
@@ -181,8 +182,8 @@ static void od_outline(void)
     xputc('\n');
   }
 
-  // buffer toggle for "same as last time" check.
-  TT.buf = (char *)((TT.buf == (char *)TT.bufs) ? TT.bufs+2 : TT.bufs);
+  // Toggle buffer for "same as last time" check.
+  TT.buf = (TT.buf == TT.bufs[0]) ? TT.bufs[1] : TT.bufs[0];
 }
 
 // Loop through input files
@@ -198,7 +199,7 @@ static void do_od(int fd, char *name)
 
   for(;;) {
     char *buf = TT.buf + TT.leftover;
-    int len = 16 - TT.leftover;
+    int len = TT.width - TT.leftover;
 
     if (toys.optflags & FLAG_N) {
       if (!TT.max_count) break;
@@ -212,7 +213,7 @@ static void do_od(int fd, char *name)
     }
     if (TT.max_count) TT.max_count -= len;
     TT.leftover += len;
-    if (TT.leftover < 16) break;
+    if (TT.leftover < TT.width) break;
 
     od_outline();
   }
@@ -264,7 +265,9 @@ void od_main(void)
 {
   struct arg_list *arg;
 
-  TT.buf = (char *)TT.bufs;
+  TT.bufs[0] = xzalloc(TT.width);
+  TT.bufs[1] = xzalloc(TT.width);
+  TT.buf = TT.bufs[0];
 
   if (!TT.address_base) TT.address_idx = 2;
   else if (0>(TT.address_idx = stridx("ndox", *TT.address_base)))
@@ -285,4 +288,9 @@ void od_main(void)
 
   if (TT.leftover) od_outline();
   od_outline();
+
+  if (CFG_TOYBOX_FREE) {
+    free(TT.bufs[0]);
+    free(TT.bufs[1]);
+  }
 }