view src/os_unix.h @ 34394:a400c8f9506f v9.1.0123

patch 9.1.0123: MS-Windows: system() may deadlock Commit: https://github.com/vim/vim/commit/52ecc76c7fa1865603f27bc838efaeaa03cad77c Author: GuyBrush <miguel.barro@live.com> Date: Wed Feb 21 20:16:38 2024 +0100 patch 9.1.0123: MS-Windows: system() may deadlock Problem: MS-Windows: system() may deadlock when calling binaries that expect stdin Solution: Ignore the SHELL_EXPAND flag (GuyBrush) This happens on binaries that expect stdin. For example: :echo system("xxd") will cause a deadlock. SHELL_EXPAND is a flag devoted to support the linux implementation of the backtick-expansion mechanism. On linux backtic-expansion relies in the function mch_expand_wildchars() (os_unix.c) that delegates on each specific shell (bash, sh, csh, zsh) the expansion. Basically it composes a shell command that does the expansion and redirects the output to a file and call_shell() it. On windows backtick-expansion is performed by Vim itself. On linux SHELL_EXPAND modifies how mch_call_shell_fork() (os_unix.c) works. This function: - relies on posix fork() to spawn a child process to execute a external command. - Child and parent process communicate using pipes (or pseudoterminal if available). User input (type ahead content) is processed in a loop only if !(SHELL_EXPAND || SHELL_COOKED). Though signals are used to detect Ctrl-C in all cases (the input loop is not necessary to interrupt the function). In the backtick-expansion the external command is the shell command that provides the expansion. For the child redirection: - SHELL_EXPAND replaces stdin, stdout & stderr to /dev/null. This is why the shell command composed includes redirection (otherwise output would be lost). - !SHELL_EXPAND replaces stdin, stdout & stderr with the parent created pipes (or pseudoterminal). Note that the use of SIGINT signal prevents mch_call_shell_fork() from hanging vim. On Windows mch_system_piped() (os_win32.c) (which is only used when the GUI is running) mimics mch_call_shell_fork() (os_unix.c). Win32 lacks fork() and relies on CreateProcessW() and only has pipe support (not pseudoterminal) which makes the implementation much different. But, the key idea is that windows lacks signals, the OS provides support for console apps but gvim is not one. The only way of detecting a Ctrl-C is actually processing user input (type ahead content). By ignoring the user input under SHELL_EXPAND the function can hang gvim. Ignoring SHELL_EXPAND flag has no consequence in Windows because as mentioned above it is only meaningful in linux. closes: #13988 Signed-off-by: GuyBrush <miguel.barro@live.com> Signed-off-by: Christian Brabandt <cb@256bit.org>
author Christian Brabandt <cb@256bit.org>
date Wed, 21 Feb 2024 20:30:02 +0100
parents 695b50472e85
children 2d7721a4d213
line wrap: on
line source

/* vi:set ts=8 sts=4 sw=4 noet:
 *
 * VIM - Vi IMproved	by Bram Moolenaar
 *
 * Do ":help uganda"  in Vim to read copying and usage conditions.
 * Do ":help credits" in Vim to see a list of people who contributed.
 */

/*
 * NextStep has a problem with configure, undefine a few things:
 */
#ifdef NeXT
# ifdef HAVE_UTIME
#  undef HAVE_UTIME
# endif
# ifdef HAVE_SYS_UTSNAME_H
#  undef HAVE_SYS_UTSNAME_H
# endif
#endif

#include <stdio.h>
#include <ctype.h>

#ifdef VAXC
# include <types.h>
# include <stat.h>
#else
# include <sys/types.h>
# include <sys/stat.h>
#endif

#ifdef HAVE_STDLIB_H
# include <stdlib.h>
#endif

#ifdef __CYGWIN__
# define WIN32UNIX	// Compiling for Win32 using Unix files.
# define BINARY_FILE_IO

# define CASE_INSENSITIVE_FILENAME
# define USE_FNAME_CASE	// Fix filename case differences.
#endif

// On AIX 4.2 there is a conflicting prototype for ioctl() in stropts.h and
// unistd.h.  This hack should fix that (suggested by Jeff George).
// But on AIX 4.3 it's alright (suggested by Jake Hamby).
#if defined(FEAT_GUI) && defined(_AIX) && !defined(_AIX43) && !defined(_NO_PROTO)
# define _NO_PROTO
#endif

#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif

#ifdef HAVE_LIBC_H
# include <libc.h>		    // for NeXT
#endif

#ifdef HAVE_SYS_PARAM_H
# include <sys/param.h>	    // defines BSD, if it's a BSD system
#endif

/*
 * Using getcwd() is preferred, because it checks for a buffer overflow.
 * Don't use getcwd() on systems do use system("sh -c pwd").  There is an
 * autoconf check for this.
 * Use getcwd() anyway if getwd() isn't present.
 */
#if defined(HAVE_GETCWD) && !(defined(BAD_GETCWD) && defined(HAVE_GETWD))
# define USE_GETCWD
#endif

// always use unlink() to remove files
#ifndef PROTO
# ifdef VMS
#  define vim_mkdir(x, y) mkdir((char *)vms_fixfilename(x), y)
#  define mch_rmdir(x)  delete((char *)vms_fixfilename(x))
#  define mch_remove(x) delete((char *)vms_fixfilename(x))
# else
#  define vim_mkdir(x, y) mkdir((char *)(x), y)
#  define mch_rmdir(x) rmdir((char *)(x))
#  define mch_remove(x) unlink((char *)(x))
# endif
#endif

// The number of arguments to a signal handler is configured here.
// It used to be a long list of almost all systems. Any system that doesn't
// have an argument???
#define SIGHASARG

#ifdef SIGHASARG
# define SIGPROTOARG	(int)
# define SIGDEFARG(s)	(int s UNUSED)
# define SIGDUMMYARG	0
#else
# define SIGPROTOARG   (void)
# define SIGDEFARG(s)  ()
# define SIGDUMMYARG
#endif

typedef void (*sighandler_T) SIGPROTOARG;

#ifdef HAVE_DIRENT_H
# include <dirent.h>
# ifndef NAMLEN
#  define NAMLEN(dirent) strlen((dirent)->d_name)
# endif
#else
# define dirent direct
# define NAMLEN(dirent) (dirent)->d_namlen
# if HAVE_SYS_NDIR_H
#  include <sys/ndir.h>
# endif
# if HAVE_SYS_DIR_H
#  include <sys/dir.h>
# endif
# if HAVE_NDIR_H
#  include <ndir.h>
# endif
#endif

#include <time.h>
#ifdef HAVE_SYS_TIME_H
# include <sys/time.h>
#endif

#include <signal.h>

#if defined(DIRSIZ) && !defined(MAXNAMLEN)
# define MAXNAMLEN DIRSIZ
#endif

#if defined(UFS_MAXNAMLEN) && !defined(MAXNAMLEN)
# define MAXNAMLEN UFS_MAXNAMLEN    // for dynix/ptx
#endif

#if defined(NAME_MAX) && !defined(MAXNAMLEN)
# define MAXNAMLEN NAME_MAX	    // for Linux before .99p3
#endif

/*
 * Note: if MAXNAMLEN has the wrong value, you will get error messages
 *	 for not being able to open the swap file.
 */
#if !defined(MAXNAMLEN)
# define MAXNAMLEN 512		    // for all other Unix
#endif

#define BASENAMELEN	(MAXNAMLEN - 5)

#ifdef HAVE_PWD_H
# include <pwd.h>
#endif

#if (defined(HAVE_SYS_RESOURCE_H) && defined(HAVE_GETRLIMIT)) \
	|| (defined(HAVE_SYS_SYSINFO_H) && defined(HAVE_SYSINFO)) \
	|| defined(HAVE_SYSCTL) || defined(HAVE_SYSCONF)
# define HAVE_TOTAL_MEM
#endif


#ifndef PROTO

#ifdef VMS
# include <unixio.h>
# include <unixlib.h>
# include <signal.h>
# include <file.h>
# include <ssdef.h>
# include <descrip.h>
# include <libclidef.h>
# include <lnmdef.h>
# include <psldef.h>
# include <prvdef.h>
# include <dvidef.h>
# include <dcdef.h>
# include <stsdef.h>
# include <iodef.h>
# include <ttdef.h>
# include <tt2def.h>
# include <jpidef.h>
# include <rms.h>
# include <trmdef.h>
# include <string.h>
# include <starlet.h>
# include <socket.h>
# include <lib$routines.h>
# include <libdef.h>
# include <libdtdef.h>

# if defined(FEAT_GUI_MOTIF)
#  define XFree XFREE
#  define XmRepTypeInstallTearOffModelCon XMREPTYPEINSTALLTEAROFFMODELCON
# endif
#endif // VMS

#ifdef HAVE_FLOCK
# include <sys/file.h>
#endif

#endif // PROTO

#ifdef VMS
typedef struct dsc$descriptor   DESC;
#endif

/*
 * Unix system-dependent file names
 */
#ifndef SYS_VIMRC_FILE
# define SYS_VIMRC_FILE "$VIM/vimrc"
#endif
#ifndef SYS_GVIMRC_FILE
# define SYS_GVIMRC_FILE "$VIM/gvimrc"
#endif
#ifndef DFLT_HELPFILE
# define DFLT_HELPFILE	"$VIMRUNTIME/doc/help.txt"
#endif
#ifndef SYS_MENU_FILE
# define SYS_MENU_FILE	"$VIMRUNTIME/menu.vim"
#endif

#ifndef USR_EXRC_FILE
# ifdef VMS
#  define USR_EXRC_FILE "sys$login:.exrc"
# else
#  define USR_EXRC_FILE "$HOME/.exrc"
# endif
#endif

#if !defined(USR_EXRC_FILE2) && defined(VMS)
# define USR_EXRC_FILE2 "sys$login:_exrc"
#endif

#ifndef USR_VIMRC_FILE
# ifdef VMS
# define USR_VIMRC_FILE  "sys$login:.vimrc"
# else
#  define USR_VIMRC_FILE "$HOME/.vimrc"
# endif
#endif


#if !defined(USR_VIMRC_FILE2)
# ifdef VMS
#  define USR_VIMRC_FILE2	"sys$login:vimfiles/vimrc"
# else
#   define USR_VIMRC_FILE2	"~/.vim/vimrc"
# endif
#endif

#if !defined(USR_VIMRC_FILE3) && defined(VMS)
# define USR_VIMRC_FILE3 "sys$login:_vimrc"
#endif

#ifndef USR_GVIMRC_FILE
# ifdef VMS
#  define USR_GVIMRC_FILE "sys$login:.gvimrc"
# else
#  define USR_GVIMRC_FILE "$HOME/.gvimrc"
# endif
#endif

#ifndef USR_GVIMRC_FILE2
# ifdef VMS
#  define USR_GVIMRC_FILE2	"sys$login:vimfiles/gvimrc"
# else
#  define USR_GVIMRC_FILE2	"~/.vim/gvimrc"
# endif
#endif

#ifdef VMS
# ifndef USR_GVIMRC_FILE3
#  define USR_GVIMRC_FILE3  "sys$login:_gvimrc"
# endif
#endif

#ifndef VIM_DEFAULTS_FILE
# define VIM_DEFAULTS_FILE "$VIMRUNTIME/defaults.vim"
#endif

#ifndef EVIM_FILE
# define EVIM_FILE	"$VIMRUNTIME/evim.vim"
#endif

#ifdef FEAT_VIMINFO
# ifndef VIMINFO_FILE
#  ifdef VMS
#   define VIMINFO_FILE  "sys$login:.viminfo"
#  else
#   define VIMINFO_FILE "$HOME/.viminfo"
#  endif
# endif
# if !defined(VIMINFO_FILE2) && defined(VMS)
#  define VIMINFO_FILE2 "sys$login:_viminfo"
# endif
#endif

#ifndef EXRC_FILE
# define EXRC_FILE	".exrc"
#endif

#ifndef VIMRC_FILE
# define VIMRC_FILE	".vimrc"
#endif

#ifdef FEAT_GUI
# ifndef GVIMRC_FILE
#  define GVIMRC_FILE	".gvimrc"
# endif
#endif

#ifndef SYNTAX_FNAME
# define SYNTAX_FNAME	"$VIMRUNTIME/syntax/%s.vim"
#endif

#ifndef DFLT_BDIR
# ifdef VMS
#  define DFLT_BDIR    "./,sys$login:,tmp:"
# else
#  define DFLT_BDIR    ".,~/tmp,~/"    // default for 'backupdir'
# endif
#endif

#ifndef DFLT_DIR
# ifdef VMS
#  define DFLT_DIR     "./,sys$login:,tmp:"
# else
#  define DFLT_DIR     ".,~/tmp,/var/tmp,/tmp" // default for 'directory'
# endif
#endif

#ifndef DFLT_VDIR
# ifdef VMS
#  define DFLT_VDIR    "sys$login:vimfiles/view"
# else
#  define DFLT_VDIR    "$HOME/.vim/view"       // default for 'viewdir'
# endif
#endif

#define DFLT_ERRORFILE		"errors.err"

#ifndef DFLT_RUNTIMEPATH

# ifdef VMS
#  define DFLT_RUNTIMEPATH      "sys$login:vimfiles,$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after,sys$login:vimfiles/after"
#  define CLEAN_RUNTIMEPATH      "$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after"
# else
#  ifdef RUNTIME_GLOBAL
#   ifdef RUNTIME_GLOBAL_AFTER
#    define DFLT_RUNTIMEPATH	"~/.vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL_AFTER ",~/.vim/after"
#    define CLEAN_RUNTIMEPATH	RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL_AFTER
#   else
#    define DFLT_RUNTIMEPATH	"~/.vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL "/after,~/.vim/after"
#    define CLEAN_RUNTIMEPATH	RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL "/after"
#   endif
#  else
#   define DFLT_RUNTIMEPATH	"~/.vim,$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after,~/.vim/after"
#   define CLEAN_RUNTIMEPATH	"$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after"
#  endif
# endif

#endif

#ifdef VMS
# ifndef VAX
#  define VMS_TEMPNAM    // to fix default .LIS extension
# endif
# define TEMPNAME       "TMP:v?XXXXXX.txt"
# define TEMPNAMELEN    28
#else
// Try several directories to put the temp files.
# define TEMPDIRNAMES  "$TMPDIR", "/tmp", ".", "$HOME"
# define TEMPNAMELEN    256
#endif

// Special wildcards that need to be handled by the shell
#define SPECIAL_WILDCHAR    "`'{"

/*
 * Unix has plenty of memory, use large buffers
 */
#define CMDBUFFSIZE 1024	// size of the command processing buffer

// Use the system path length if it makes sense.
#if defined(PATH_MAX) && (PATH_MAX > 1000)
# define MAXPATHL	PATH_MAX
#else
# define MAXPATHL	1024
#endif

#define CHECK_INODE		// used when checking if a swap file already
				// exists for a file
#ifdef VMS  // Use less memory because of older systems
# ifndef DFLT_MAXMEM
#  define DFLT_MAXMEM (2*1024)
# endif
# ifndef DFLT_MAXMEMTOT
#  define DFLT_MAXMEMTOT (5*1024)
# endif
#else
# ifndef DFLT_MAXMEM
#  define DFLT_MAXMEM	(5*1024)	 // use up to 5 Mbyte for a buffer
# endif
# ifndef DFLT_MAXMEMTOT
#  define DFLT_MAXMEMTOT	(10*1024)    // use up to 10 Mbyte for Vim
# endif
#endif

// memmove() is not present on all systems, use memmove, bcopy or memcpy.
// Some systems have (void *) arguments, some (char *). If we use (char *) it
// works for all
#if defined(USEMEMMOVE) || (!defined(USEBCOPY) && !defined(USEMEMCPY))
# define mch_memmove(to, from, len) memmove((char *)(to), (char *)(from), len)
#else
# ifdef USEBCOPY
#  define mch_memmove(to, from, len) bcopy((char *)(from), (char *)(to), len)
# else
    // ifdef USEMEMCPY
#   define mch_memmove(to, from, len) memcpy((char *)(to), (char *)(from), len)
# endif
#endif

#ifndef PROTO
# ifdef HAVE_RENAME
#  define mch_rename(src, dst) rename(src, dst)
# else
int mch_rename(const char *src, const char *dest);
# endif
# ifndef VMS
#  ifdef __MVS__
  // on OS390 Unix getenv() doesn't return a pointer to persistent
  // storage -> use __getenv()
#   define mch_getenv(x) (char_u *)__getenv((char *)(x))
#  else
#   define mch_getenv(x) (char_u *)getenv((char *)(x))
#  endif
#  define mch_setenv(name, val, x) setenv(name, val, x)
# endif
#endif

// Note: Some systems need both string.h and strings.h (Savage).  However,
// some systems can't handle both, only use string.h in that case.
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#if defined(HAVE_STRINGS_H) && !defined(NO_STRINGS_WITH_STRING_H)
# include <strings.h>
#endif

#if defined(HAVE_SETJMP_H)
# include <setjmp.h>
# ifdef HAVE_SIGSETJMP
#  define JMP_BUF sigjmp_buf
#  define SETJMP(x) sigsetjmp((x), 1)
#  define LONGJMP siglongjmp
# else
#  define JMP_BUF jmp_buf
#  define SETJMP(x) setjmp(x)
#  define LONGJMP longjmp
# endif
#endif

#ifndef HAVE_DUP
# define HAVE_DUP		// have dup()
#endif
#define HAVE_ST_MODE		// have stat.st_mode

// We have three kinds of ACL support.
#define HAVE_ACL (HAVE_POSIX_ACL || HAVE_SOLARIS_ACL || HAVE_AIX_ACL)