From bb0e7fabcaed9a7e71e30f05e638e9f243cdb13e Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?P=C3=A1draig=20Brady?= <P@draigBrady.com>

Date: Mon, 25 Jan 2021 14:12:48 +0000

Subject: [PATCH] split: fix --number=K/N to output correct part of file

This functionality regressed with the adjustments

in commit v8.25-4-g62e7af032

* src/split.c (bytes_chunk_extract): Account for already read data

when seeking into the file.

* tests/split/b-chunk.sh: Use the hidden ---io-blksize option,

to test this functionality.

Fixes https://bugs.gnu.org/46048

Upstream-commit: bb21daa125aeb4e32546309d370918ca47e612db

Signed-off-by: Kamil Dudka <kdudka@redhat.com>

---

 src/split.c            |  2 +-

 tests/split/b-chunk.sh | 45 ++++++++++++++++++++++++------------------

 2 files changed, 27 insertions(+), 20 deletions(-)

diff --git a/src/split.c b/src/split.c

index 09e610b..19248f6 100644

--- a/src/split.c

+++ b/src/split.c

@@ -1001,7 +1001,7 @@ bytes_chunk_extract (uintmax_t k, uintmax_t n, char *buf, size_t bufsize,

     }

   else

     {

-      if (lseek (STDIN_FILENO, start, SEEK_CUR) < 0)

+      if (lseek (STDIN_FILENO, start - initial_read, SEEK_CUR) < 0)

         die (EXIT_FAILURE, errno, "%s", quotef (infile));

       initial_read = SIZE_MAX;

     }

diff --git a/tests/split/b-chunk.sh b/tests/split/b-chunk.sh

index 864ce55..39a6799 100755

--- a/tests/split/b-chunk.sh

+++ b/tests/split/b-chunk.sh

@@ -35,32 +35,39 @@ split -e -n 10 /dev/null || fail=1

 returns_ 1 stat x?? 2>/dev/null || fail=1

 printf '1\n2\n3\n4\n5\n' > input || framework_failure_

+printf '1\n2' > exp-1 || framework_failure_

+printf '\n3\n' > exp-2 || framework_failure_

+printf '4\n5\n' > exp-3 || framework_failure_

 for file in input /proc/version /sys/kernel/profiling; do

   test -f $file || continue

-  split -n 3 $file > out || fail=1

-  split -n 1/3 $file > b1 || fail=1

-  split -n 2/3 $file > b2 || fail=1

-  split -n 3/3 $file > b3 || fail=1

+  for blksize in 1 2 4096; do

+    if ! test "$file" = 'input'; then

+      # For /proc like files we must be able to read all

+      # into the internal buffer to be able to determine size.

+      test "$blksize" = 4096 || continue

+    fi

-  case $file in

-    input)

-      printf '1\n2' > exp-1

-      printf '\n3\n' > exp-2

-      printf '4\n5\n' > exp-3

+    split -n 3 ---io-blksize=$blksize $file > out || fail=1

+    split -n 1/3 ---io-blksize=$blksize $file > b1 || fail=1

+    split -n 2/3 ---io-blksize=$blksize $file > b2 || fail=1

+    split -n 3/3 ---io-blksize=$blksize $file > b3 || fail=1

-      compare exp-1 xaa || fail=1

-      compare exp-2 xab || fail=1

-      compare exp-3 xac || fail=1

-      ;;

-  esac

+    case $file in

+      input)

+        compare exp-1 xaa || fail=1

+        compare exp-2 xab || fail=1

+        compare exp-3 xac || fail=1

+        ;;

+    esac

-  compare xaa b1 || fail=1

-  compare xab b2 || fail=1

-  compare xac b3 || fail=1

-  cat xaa xab xac | compare - $file || fail=1

-  test -f xad && fail=1

+    compare xaa b1 || fail=1

+    compare xab b2 || fail=1

+    compare xac b3 || fail=1

+    cat xaa xab xac | compare - $file || fail=1

+    test -f xad && fail=1

+  done

 done

 Exit $fail

-- 

2.26.2