Mercurial > vim
view src/create_cmdidxs.vim @ 33815:08f9e1eac4cf v9.0.2123
patch 9.0.2123: Problem with initializing the length of range() lists
Commit: https://github.com/vim/vim/commit/df63da98d8dc284b1c76cfe1b17fa0acbd6094d8
Author: Christian Brabandt <cb@256bit.org>
Date: Thu Nov 23 20:14:28 2023 +0100
patch 9.0.2123: Problem with initializing the length of range() lists
Problem: Problem with initializing the length of range() lists
Solution: Set length explicitly when it shouldn't contain any items
range() may cause a wrong calculation of list length, which may later
then cause a segfault in list_find(). This is usually not a problem,
because range_list_materialize() calculates the length, when it
materializes the list.
In addition, in list_find() when the length of the range was wrongly
initialized, it may seem to be valid, so the check for list index
out-of-bounds will not be true, because it is called before the list is
actually materialized. And so we may eventually try to access a null
pointer, causing a segfault.
So this patch does 3 things:
- In f_range(), when we know that the list should be empty, explicitly
set the list->lv_len value to zero. This should happen, when
start is larger than end (in case the stride is positive) or
end is larger than start when the stride is negative.
This should fix the underlying issue properly. However,
- as a safety measure, let's check that the requested index is not
out of range one more time, after the list has been materialized
and return NULL in case it suddenly is.
- add a few more tests to verify the behaviour.
fixes: #13557
closes: #13563
Co-authored-by: Tim Pope <tpope@github.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
author | Christian Brabandt <cb@256bit.org> |
---|---|
date | Thu, 23 Nov 2023 20:30:07 +0100 |
parents | 72ce5ca82a75 |
children |
line wrap: on
line source
" This script generates the tables cmdidxs1[] and cmdidxs2[][] which, " given a Ex command, determine the first value to probe to find " a matching command in cmdnames[] based on the first character " and the first 2 characters of the command. " This is used to speed up lookup in cmdnames[]. " " Script should be run every time new Ex commands are added in Vim, " from the src/vim directory, since it reads commands from "ex_cmds.h". let cmds = [] let skipped_cmds = 0 let lines = readfile('ex_cmds.h') let idx = 0 while idx < len(lines) let line = lines[idx] if line =~ '^EXCMD(CMD_' let m = matchlist(line, '^EXCMD(CMD_\S*,\s*"\([a-z][^"]*\)"') if len(m) >= 2 let cmds += [ m[1] ] else let skipped_cmds += 1 endif let idx += 1 let flags = lines[idx] let idx += 1 let addr_type = lines[idx] if flags =~ '\<EX_RANGE\>' if addr_type =~ 'ADDR_NONE' echoerr 'ex_cmds.h:' .. (idx - 1) .. ': Using EX_RANGE with ADDR_NONE: ' .. line endif else if addr_type !~ 'ADDR_NONE' echoerr 'ex_cmds.h:' .. (idx - 1) .. ': Missing ADDR_NONE: ' .. line endif endif if flags =~ '\<EX_DFLALL\>' && (addr_type =~ 'ADDR_OTHER' || addr_type =~ 'ADDR_NONE') echoerr 'ex_cmds.h:' .. (idx - 1) .. ': Missing misplaced EX_DFLALL: ' .. line endif endif let idx += 1 endwhile let cmdidxs1 = {} let cmdidxs2 = {} for i in range(len(cmds) - 1, 0, -1) let cmd = cmds[i] let c1 = cmd[0] " First character of command let c2 = cmd[1] " Second character of command (if any) let cmdidxs1{c1} = i if c2 >= 'a' && c2 <= 'z' let cmdidxs2{c1}{c2} = i endif endfor let output = [ '/* Automatically generated code by create_cmdidxs.vim' ] let output += [ ' *' ] let output += [ ' * Table giving the index of the first command in cmdnames[] to lookup' ] let output += [ ' * based on the first letter of a command.' ] let output += [ ' */' ] let output += [ 'static const unsigned short cmdidxs1[26] =' ] let output += [ '{' ] let a_to_z = map(range(char2nr('a'), char2nr('z')), 'nr2char(v:val)') for c1 in a_to_z let line = ' /* ' . c1 . ' */ ' . cmdidxs1{c1} . ((c1 == 'z') ? '' : ',') let output += [ line ] endfor let output += [ '};' ] let output += [ '' ] let output += [ '/*' ] let output += [ ' * Table giving the index of the first command in cmdnames[] to lookup' ] let output += [ ' * based on the first 2 letters of a command.' ] let output += [ ' * Values in cmdidxs2[c1][c2] are relative to cmdidxs1[c1] so that they' ] let output += [ ' * fit in a byte.' ] let output += [ ' */' ] let output += [ 'static const unsigned char cmdidxs2[26][26] =' ] let output += [ '{ /* a b c d e f g h i j k l m n o p q r s t u v w x y z */' ] for c1 in a_to_z let line = ' /* ' . c1 . ' */ {' for c2 in a_to_z if exists('cmdidxs2{c1}{c2}') let line .= printf('%3d', cmdidxs2{c1}{c2} - cmdidxs1{c1}) else let line .= ' 0' endif let line .= (c2 == 'z') ? '' : ',' endfor let line .= ' }' . ((c1 == 'z') ? '' : ',') let output += [ line ] endfor let output += [ '};' ] let output += [ '' ] let output += [ 'static const int command_count = ' . (len(cmds) + skipped_cmds) . ';' ] call writefile(output, "ex_cmdidxs.h") quit