From 88fb25f0176b094da91385c02122aaf0497fe710 Mon Sep 17 00:00:00 2001
From: Rob Landley <rob@landley.net>
Date: Mon, 19 Sep 2022 09:51:53 -0500
Subject: [PATCH] Make -c 0 disable columns and -g 0 disable groups.

Add a test that circa 1998 xxd doesn't pass, but newer ones should. Skip
on host for now, fix when regularly testing on a distro that passes.
---
 tests/xxd.test   |  6 ++++++
 toys/other/xxd.c | 25 +++++++++++++------------
 2 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/tests/xxd.test b/tests/xxd.test
index d4ae10b8..d4862784 100755
--- a/tests/xxd.test
+++ b/tests/xxd.test
@@ -30,6 +30,12 @@ testing "-o 0x8000" "xxd -o 0x8000 file1" "00008000: 7468 6973 2069 7320 736f 6d
 
 testing "-p" "xxd -p file1" "7468697320697320736f6d6520746578740a\n" "" ""
 
+# TODO: remove toyonly when distro catches up
+toyonly testing "-pc0" "xxd -pc0" \
+  "73686f77203830206865782064696769747320776974686f757420776f72647772617070696e670a\n" \
+  "" "show 80 hex digits without wordwrapping\n"
+toyonly testing "-pc0 long" "xxd -pc0 | wc -c" "97787\n" "" "$(seq 1 10000)"
+
 testing "-s" "xxd -s 13 file1" "0000000d: 7465 7874 0a                             text.\n" "" ""
 
 testing "-r" "echo -e '    00000000: 7468 6973 2069 7320 736f 6d65 2074 6578  this is some tex\n00000010: 740a                                     t.' | xxd -r" "this is some text\n" "" ""
diff --git a/toys/other/xxd.c b/toys/other/xxd.c
index 1809a6db..bb0a8e26 100644
--- a/toys/other/xxd.c
+++ b/toys/other/xxd.c
@@ -10,7 +10,7 @@
  * xxd -p "plain" output:
  *   "4c696e75782076657273696f6e20342e392e302d342d616d643634202864"
 
-USE_XXD(NEWTOY(xxd, ">1c#<0>256l#o#g#<1=2iprs#[!rs]", TOYFLAG_USR|TOYFLAG_BIN))
+USE_XXD(NEWTOY(xxd, ">1c#<0>256l#o#g#<0=2iprs#[!rs]", TOYFLAG_USR|TOYFLAG_BIN))
 
 config XXD
   bool "xxd"
@@ -26,7 +26,7 @@ config XXD
     -i	Output include file (CSV hex bytes, plus C header/footer if not stdin)
     -l n	Limit of n bytes before stopping (default is no limit)
     -o n	Add n to display offset
-    -p	Plain hexdump (30 bytes/line, no grouping)
+    -p	Plain hexdump (30 bytes/line, no grouping. With -c 0 no wrap/group)
     -r	Reverse operation: turn a hexdump into a binary file
     -s n	Skip to offset n
 */
@@ -42,7 +42,7 @@ static void do_xxd(int fd, char *name)
 {
   long long pos = 0;
   long long limit = TT.l;
-  int i, len, space;
+  int i, len, space, c = TT.c ? : sizeof(toybuf);
 
   if (FLAG(s)) {
     xlseek(fd, TT.s, SEEK_SET);
@@ -51,15 +51,16 @@ static void do_xxd(int fd, char *name)
   }
 
   while (0<(len = readall(fd, toybuf,
-                          (limit && limit-pos<TT.c)?limit-pos:TT.c)))
+                          (limit && limit-pos<c)?limit-pos:c)))
   {
     if (!FLAG(p)) printf("%08llx: ", TT.o + pos);
     pos += len;
-    space = 2*TT.c+(TT.c+TT.g-1)/TT.g+1;
+    space = 2*TT.c;
+    space += TT.g ? (TT.c+TT.g-1)/TT.g+1 : 2;
 
     for (i=0; i<len;) {
-      space -= printf("%02x", toybuf[i]);
-      if (!(++i%TT.g)) {
+      space -= printf("%02x", toybuf[i++]);
+      if (TT.g && !(i%TT.g)) {
         putchar(' ');
         space--;
       }
@@ -70,8 +71,9 @@ static void do_xxd(int fd, char *name)
       for (i = 0; i<len; i++)
         putchar((toybuf[i]>=' ' && toybuf[i]<='~') ? toybuf[i] : '.');
     }
-    putchar('\n');
+    if (TT.c || !FLAG(p)) putchar('\n');
   }
+  if (!TT.c && FLAG(p)) putchar('\n');
   if (len<0) perror_exit("read");
 }
 
@@ -125,7 +127,7 @@ static void do_xxd_reverse(int fd, char *name)
     // A plain hexdump can have as many bytes per line as you like,
     // but a non-plain hexdump assumes garbage after it's seen the
     // specified number of bytes.
-    while (FLAG(p) || col < TT.c) {
+    while (FLAG(p) || !TT.c || col < TT.c) {
       int n1, n2;
 
       // If we're at EOF or EOL or we read some non-hex...
@@ -155,10 +157,9 @@ static void do_xxd_reverse(int fd, char *name)
 
 void xxd_main(void)
 {
-  if (!TT.c) TT.c = FLAG(i) ? 12 : 16;
-
   // Plain style is 30 bytes/line, no grouping.
-  if (FLAG(p)) TT.c = TT.g = 30;
+  if (!FLAG(c)) TT.c = FLAG(p) ? 30 : FLAG(i) ? 12 : 16;
+  if (FLAG(p) && !FLAG(g)) TT.g = TT.c;
 
   loopfiles(toys.optargs,
     FLAG(r) ? do_xxd_reverse : (FLAG(i) ? do_xxd_include : do_xxd));
-- 
2.39.2