git/string-list.c, branch v2.16.2

cleanup: fix possible overflow errors in binary search

2017-10-09T23:57:24Z

A common mistake when writing binary search is to allow possible integer overflow by using the simple average: mid = (min + max) / 2; Instead, use the overflow-safe version: mid = min + (max - min) / 2; This translation is safe since the operation occurs inside a loop conditioned on "min < max". The included changes were found using the following git grep: git grep '/ *2;' '*.c' Making this cleanup will prevent future review friction when a new binary search is contructed based on existing code. Signed-off-by: Derrick Stolee Reviewed-by: Jeff King Signed-off-by: Junio C Hamano

use MOVE_ARRAY

2017-07-17T21:54:56Z

Simplify the code for moving members inside of an array and make it more robust by using the helper macro MOVE_ARRAY. It calculates the size based on the specified number of elements for us and supports NULL pointers when that number is zero. Raw memmove(3) calls with NULL can cause the compiler to (over-eagerly) optimize out later NULL checks. This patch was generated with contrib/coccinelle/array.cocci and spatch (Coccinelle). Signed-off-by: Rene Scharfe Signed-off-by: Junio C Hamano

Merge branch 'bw/forking-and-threading'

2017-05-30T02:16:41Z

The "run-command" API implementation has been made more robust against dead-locking in a threaded environment. * bw/forking-and-threading: usage.c: drop set_error_handle() run-command: restrict PATH search to executable files run-command: expose is_executable function run-command: block signals between fork and execve run-command: add note about forking and threading run-command: handle dup2 and close errors in child run-command: eliminate calls to error handling functions in child run-command: don't die in child when duping /dev/null run-command: prepare child environment before forking string-list: add string_list_remove function run-command: use the async-signal-safe execv instead of execvp run-command: prepare command before forking t0061: run_command executes scripts without a #! line t5550: use write_script to generate post-update hook

Merge branch 'jh/string-list-micro-optim'

2017-04-24T05:07:47Z

The string-list API used a custom reallocation strategy that was very inefficient, instead of using the usual ALLOC_GROW() macro, which has been fixed. * jh/string-list-micro-optim: string-list: use ALLOC_GROW macro when reallocing string_list

string-list: add string_list_remove function

2017-04-21T00:55:32Z

Teach string-list to be able to remove a string from a sorted 'struct string_list'. Signed-off-by: Brandon Williams Signed-off-by: Junio C Hamano

string-list: use ALLOC_GROW macro when reallocing string_list

2017-04-15T09:04:41Z

Use ALLOC_GROW() macro when reallocing a string_list array rather than simply increasing it by 32. This is a performance optimization. During status on a very large repo and there are many changes, a significant percentage of the total run time is spent reallocing the wt_status.changes array. This change decreases the time in wt_status_collect_changes_worktree() from 125 seconds to 45 seconds on my very large repository. This produced a modest gain on my 1M file artificial repo, but broke even on linux.git. Test HEAD^^ HEAD --------------------------------------------------------------------------------------- 0005.2: read-tree status br_ballast (1000001) 8.29(5.62+2.62) 8.22(5.57+2.63) -0.8% Signed-off-by: Jeff Hostetler Signed-off-by: Junio C Hamano

string-list: use QSORT_S in string_list_sort()

2017-01-23T19:02:38Z

Pass the comparison function to cmp_items() via the context parameter of qsort_s() instead of using a global variable. That allows calling string_list_sort() from multiple parallel threads. Our qsort_s() in compat/ is slightly slower than qsort(1) from glibc 2.24 for sorting lots of lines: Test HEAD^ HEAD --------------------------------------------------------------------- 0071.2: sort(1) 0.10(0.22+0.01) 0.09(0.21+0.00) -10.0% 0071.3: string_list_sort() 0.16(0.15+0.01) 0.17(0.15+0.00) +6.3% GNU sort(1) version 8.26 is significantly faster because it uses multiple parallel threads; with the unportable option --parallel=1 it becomes slower: Test HEAD^ HEAD -------------------------------------------------------------------- 0071.2: sort(1) 0.21(0.18+0.01) 0.20(0.18+0.01) -4.8% 0071.3: string_list_sort() 0.16(0.13+0.02) 0.17(0.15+0.01) +6.3% There is some instability -- the numbers for the sort(1) check shouldn't be affected by this patch. Anyway, the performance of our qsort_s() implementation is apparently good enough, at least for this test. Signed-off-by: Rene Scharfe Signed-off-by: Junio C Hamano

use QSORT

2016-09-29T22:42:18Z

Apply the semantic patch contrib/coccinelle/qsort.cocci to the code base, replacing calls of qsort(3) with QSORT. The resulting code is shorter and supports empty arrays with NULL pointers. Signed-off-by: Rene Scharfe Signed-off-by: Junio C Hamano

string_list: use string-list API in unsorted_string_list_lookup()

2016-04-25T18:48:27Z

Using the string-list API in function unsorted_string_list_lookup() makes the code more readable. Signed-off-by: Ralf Thielow Acked-by: Johannes Schindelin Signed-off-by: Junio C Hamano

Merge branch 'sb/string-list'

2014-12-22T20:27:30Z

API simplification. * sb/string-list: string_list: remove string_list_insert_at_index() from its API mailmap: use higher level string list functions string_list: document string_list_(insert,lookup)