view src/if_cscope.c @ 33004:50e7d33c40f9 v9.0.1794

patch 9.0.1794: autoconf: not correctly detecing include dirs Commit: https://github.com/vim/vim/commit/74e1dada4199b2d9e68ccaafdb7895c85b4b08f1 Author: Illia Bobyr <illia.bobyr@gmail.com> Date: Sun Aug 27 18:26:54 2023 +0200 patch 9.0.1794: autoconf: not correctly detecing include dirs Problem: autoconf: not correctly detecing include dirs Solution: make use of python3 to generate includedirs configure: Python3: Use sysconfig for -I It seems better to use tools provided by Python for determining the include directories, rather than construct them "manually". Current system is broken when using virtual environments for python 3.11.4. It used to work before, but now it detects a incorrect value for `-I`. It would probably make sense to switch to a similar logic for lib folders, that is for the `-l` switch. There are also `sysconfig.get_config_h_filename()` and `sysconfig.get_makefile_filename()`, that could replace more Python specific logic in the current `configure{.ac,}`. sysconfig provides the necessary tools since Python 2.7. closes: #12889 Signed-off-by: Christian Brabandt <cb@256bit.org> Co-authored-by: Illia Bobyr <illia.bobyr@gmail.com>
author Christian Brabandt <cb@256bit.org>
date Sun, 27 Aug 2023 18:45:03 +0200
parents 695b50472e85
children a9e71b25d1b1
line wrap: on
line source

/* vi:set ts=8 sts=4 sw=4 noet:
 *
 * CSCOPE support for Vim added by Andy Kahn <kahn@zk3.dec.com>
 * Ported to Win32 by Sergey Khorev <sergey.khorev@gmail.com>
 *
 * The basic idea/structure of cscope for Vim was borrowed from Nvi.  There
 * might be a few lines of code that look similar to what Nvi has.
 *
 * See README.txt for an overview of the Vim source code.
 */

#include "vim.h"

#if defined(FEAT_CSCOPE) || defined(PROTO)

#include <sys/types.h>
#include <sys/stat.h>
#if defined(UNIX)
# include <sys/wait.h>
#endif

#if defined (MSWIN)
# ifndef WIN32_LEAN_AND_MEAN
#  define WIN32_LEAN_AND_MEAN
# endif
# include <windows.h>
#endif

#define CSCOPE_SUCCESS		0
#define CSCOPE_FAILURE		-1

#define	CSCOPE_DBFILE		"cscope.out"
#define	CSCOPE_PROMPT		">> "

/*
 * See ":help cscope-find" for the possible queries.
 */

typedef struct {
    char *  name;
    int     (*func)(exarg_T *eap);
    char *  help;
    char *  usage;
    int	    cansplit;		// if supports splitting window
} cscmd_T;

typedef struct csi {
    char *	    fname;	// cscope db name
    char *	    ppath;	// path to prepend (the -P option)
    char *	    flags;	// additional cscope flags/options (e.g, -p2)
#if defined(UNIX)
    pid_t	    pid;	// PID of the connected cscope process.
    dev_t	    st_dev;	// ID of dev containing cscope db
    ino_t	    st_ino;	// inode number of cscope db
#else
# if defined(MSWIN)
    DWORD	    pid;	// PID of the connected cscope process.
    HANDLE	    hProc;	// cscope process handle
    DWORD	    nVolume;	// Volume serial number, instead of st_dev
    DWORD	    nIndexHigh;	// st_ino has no meaning in the Windows
    DWORD	    nIndexLow;
# endif
#endif

    FILE *	    fr_fp;	// from cscope: FILE.
    FILE *	    to_fp;	// to cscope: FILE.
} csinfo_T;

typedef enum { Add, Find, Help, Kill, Reset, Show } csid_e;

typedef enum {
    Store,
    Get,
    Free,
    Print
} mcmd_e;

static int	    cs_add(exarg_T *eap);
static int	    cs_add_common(char *, char *, char *);
static int	    cs_check_for_connections(void);
static int	    cs_check_for_tags(void);
static int	    cs_cnt_connections(void);
static int	    cs_create_connection(int i);
#ifdef FEAT_QUICKFIX
static void	    cs_file_results(FILE *, int *);
#endif
static void	    cs_fill_results(char *, int , int *, char ***,
			char ***, int *);
static int	    cs_find(exarg_T *eap);
static int	    cs_find_common(char *opt, char *pat, int, int, int, char_u *cmdline);
static int	    cs_help(exarg_T *eap);
static int	    cs_insert_filelist(char *, char *, char *,
			stat_T *);
static int	    cs_kill(exarg_T *eap);
static void	    cs_kill_execute(int, char *);
static cscmd_T *    cs_lookup_cmd(exarg_T *eap);
static char *	    cs_make_vim_style_matches(char *, char *,
			char *, char *);
static char *	    cs_manage_matches(char **, char **, int, mcmd_e);
static void	    cs_print_tags_priv(char **, char **, int);
static int	    cs_read_prompt(int);
static void	    cs_release_csp(int, int freefnpp);
static int	    cs_reset(exarg_T *eap);
static char *	    cs_resolve_file(int, char *);
static int	    cs_show(exarg_T *eap);


static csinfo_T *   csinfo = NULL;
static int	    csinfo_size = 0;	// number of items allocated in
					// csinfo[]

static int	    eap_arg_len;    // length of eap->arg, set in
				    // cs_lookup_cmd()
static cscmd_T	    cs_cmds[] =
{
    { "add",	cs_add,
		N_("Add a new database"),     "add file|dir [pre-path] [flags]", 0 },
    { "find",	cs_find,
		N_("Query for a pattern"),    "find a|c|d|e|f|g|i|s|t name", 1 },
    { "help",	cs_help,
		N_("Show this message"),      "help", 0 },
    { "kill",	cs_kill,
		N_("Kill a connection"),      "kill #", 0 },
    { "reset",	cs_reset,
		N_("Reinit all connections"), "reset", 0 },
    { "show",	cs_show,
		N_("Show connections"),       "show", 0 },
    { NULL, NULL, NULL, NULL, 0 }
};

    static void
cs_usage_msg(csid_e x)
{
    (void)semsg(_(e_usage_cscope_str), cs_cmds[(int)x].usage);
}

static enum
{
    EXP_CSCOPE_SUBCMD,	// expand ":cscope" sub-commands
    EXP_SCSCOPE_SUBCMD,	// expand ":scscope" sub-commands
    EXP_CSCOPE_FIND,	// expand ":cscope find" arguments
    EXP_CSCOPE_KILL	// expand ":cscope kill" arguments
} expand_what;

/*
 * Function given to ExpandGeneric() to obtain the cscope command
 * expansion.
 */
    char_u *
get_cscope_name(expand_T *xp UNUSED, int idx)
{
    int		current_idx;
    int		i;

    switch (expand_what)
    {
    case EXP_CSCOPE_SUBCMD:
	// Complete with sub-commands of ":cscope":
	// add, find, help, kill, reset, show
	return (char_u *)cs_cmds[idx].name;
    case EXP_SCSCOPE_SUBCMD:
	// Complete with sub-commands of ":scscope": same sub-commands as
	// ":cscope" but skip commands which don't support split windows
	for (i = 0, current_idx = 0; cs_cmds[i].name != NULL; i++)
	    if (cs_cmds[i].cansplit)
		if (current_idx++ == idx)
		    break;
	return (char_u *)cs_cmds[i].name;
    case EXP_CSCOPE_FIND:
	{
	    const char *query_type[] =
	    {
		"a", "c", "d", "e", "f", "g", "i", "s", "t", NULL
	    };

	    // Complete with query type of ":cscope find {query_type}".
	    // {query_type} can be letters (c, d, ... a) or numbers (0, 1,
	    // ..., 9) but only complete with letters, since numbers are
	    // redundant.
	    return (char_u *)query_type[idx];
	}
    case EXP_CSCOPE_KILL:
	{
	    static char	connection[5];

	    // ":cscope kill" accepts connection numbers or partial names of
	    // the pathname of the cscope database as argument.  Only complete
	    // with connection numbers. -1 can also be used to kill all
	    // connections.
	    for (i = 0, current_idx = 0; i < csinfo_size; i++)
	    {
		if (csinfo[i].fname == NULL)
		    continue;
		if (current_idx++ == idx)
		{
		    vim_snprintf(connection, sizeof(connection), "%d", i);
		    return (char_u *)connection;
		}
	    }
	    return (current_idx == idx && idx > 0) ? (char_u *)"-1" : NULL;
	}
    default:
	return NULL;
    }
}

/*
 * Handle command line completion for :cscope command.
 */
    void
set_context_in_cscope_cmd(
    expand_T	*xp,
    char_u	*arg,
    cmdidx_T	cmdidx)
{
    char_u	*p;

    // Default: expand subcommands
    xp->xp_context = EXPAND_CSCOPE;
    xp->xp_pattern = arg;
    expand_what = (cmdidx == CMD_scscope)
			? EXP_SCSCOPE_SUBCMD : EXP_CSCOPE_SUBCMD;

    if (*arg == NUL)
	return;

    // (part of) subcommand already typed
    p = skiptowhite(arg);
    if (*p == NUL)
	return;

    // past first word
    xp->xp_pattern = skipwhite(p);
    if (*skiptowhite(xp->xp_pattern) != NUL)
	xp->xp_context = EXPAND_NOTHING;
    else if (STRNICMP(arg, "add", p - arg) == 0)
	xp->xp_context = EXPAND_FILES;
    else if (STRNICMP(arg, "kill", p - arg) == 0)
	expand_what = EXP_CSCOPE_KILL;
    else if (STRNICMP(arg, "find", p - arg) == 0)
	expand_what = EXP_CSCOPE_FIND;
    else
	xp->xp_context = EXPAND_NOTHING;
}

/*
 * Find the command, print help if invalid, and then call the corresponding
 * command function.
 */
    static void
do_cscope_general(
    exarg_T	*eap,
    int		make_split UNUSED) // whether to split window
{
    cscmd_T *cmdp;

    if ((cmdp = cs_lookup_cmd(eap)) == NULL)
    {
	cs_help(eap);
	return;
    }

    if (make_split)
    {
	if (!cmdp->cansplit)
	{
	    (void)msg_puts(_("This cscope command does not support splitting the window.\n"));
	    return;
	}
	postponed_split = -1;
	postponed_split_flags = cmdmod.cmod_split;
	postponed_split_tab = cmdmod.cmod_tab;
    }

    cmdp->func(eap);

    postponed_split_flags = 0;
    postponed_split_tab = 0;
}

/*
 * Implementation of ":cscope" and ":lcscope"
 */
    void
ex_cscope(exarg_T *eap)
{
    do_cscope_general(eap, FALSE);
}

/*
 * Implementation of ":scscope". Same as ex_cscope(), but splits window, too.
 */
    void
ex_scscope(exarg_T *eap)
{
    do_cscope_general(eap, TRUE);
}

/*
 * Implementation of ":cstag"
 */
    void
ex_cstag(exarg_T *eap)
{
    int ret = FALSE;

    if (*eap->arg == NUL)
    {
	(void)emsg(_(e_usage_cstag_ident));
	return;
    }

    switch (p_csto)
    {
    case 0 :
	if (cs_check_for_connections())
	{
	    ret = cs_find_common("g", (char *)(eap->arg), eap->forceit, FALSE,
						       FALSE, *eap->cmdlinep);
	    if (ret == FALSE)
	    {
		cs_free_tags();
		if (msg_col)
		    msg_putchar('\n');

		if (cs_check_for_tags())
		    ret = do_tag(eap->arg, DT_JUMP, 0, eap->forceit, FALSE);
	    }
	}
	else if (cs_check_for_tags())
	{
	    ret = do_tag(eap->arg, DT_JUMP, 0, eap->forceit, FALSE);
	}
	break;
    case 1 :
	if (cs_check_for_tags())
	{
	    ret = do_tag(eap->arg, DT_JUMP, 0, eap->forceit, FALSE);
	    if (ret == FALSE)
	    {
		if (msg_col)
		    msg_putchar('\n');

		if (cs_check_for_connections())
		{
		    ret = cs_find_common("g", (char *)(eap->arg), eap->forceit,
						FALSE, FALSE, *eap->cmdlinep);
		    if (ret == FALSE)
			cs_free_tags();
		}
	    }
	}
	else if (cs_check_for_connections())
	{
	    ret = cs_find_common("g", (char *)(eap->arg), eap->forceit, FALSE,
						       FALSE, *eap->cmdlinep);
	    if (ret == FALSE)
		cs_free_tags();
	}
	break;
    default :
	break;
    }

    if (!ret)
    {
	(void)emsg(_(e_cstag_tag_not_founc));
#if defined(FEAT_QUICKFIX)
	g_do_tagpreview = 0;
#endif
    }

}


/*
 * This simulates a vim_fgets(), but for cscope, returns the next line
 * from the cscope output.  should only be called from find_tags()
 *
 * returns TRUE if eof, FALSE otherwise
 */
    int
cs_fgets(char_u *buf, int size)
{
    char *p;

    if ((p = cs_manage_matches(NULL, NULL, -1, Get)) == NULL)
	return TRUE;
    vim_strncpy(buf, (char_u *)p, size - 1);

    return FALSE;
}


/*
 * Called only from do_tag(), when popping the tag stack.
 */
    void
cs_free_tags(void)
{
    cs_manage_matches(NULL, NULL, -1, Free);
}


/*
 * Called from do_tag().
 */
    void
cs_print_tags(void)
{
    cs_manage_matches(NULL, NULL, -1, Print);
}


/*
 * "cscope_connection([{num} , {dbpath} [, {prepend}]])" function
 *
 *		Checks for the existence of a |cscope| connection.  If no
 *		parameters are specified, then the function returns:
 *
 *		0, if cscope was not available (not compiled in), or if there
 *		are no cscope connections; or
 *		1, if there is at least one cscope connection.
 *
 *		If parameters are specified, then the value of {num}
 *		determines how existence of a cscope connection is checked:
 *
 *		{num}	Description of existence check
 *		-----	------------------------------
 *		0	Same as no parameters (e.g., "cscope_connection()").
 *		1	Ignore {prepend}, and use partial string matches for
 *			{dbpath}.
 *		2	Ignore {prepend}, and use exact string matches for
 *			{dbpath}.
 *		3	Use {prepend}, use partial string matches for both
 *			{dbpath} and {prepend}.
 *		4	Use {prepend}, use exact string matches for both
 *			{dbpath} and {prepend}.
 *
 *		Note: All string comparisons are case sensitive!
 */
#if defined(FEAT_EVAL) || defined(PROTO)
    static int
cs_connection(int num, char_u *dbpath, char_u *ppath)
{
    int i;

    if (num < 0 || num > 4 || (num > 0 && !dbpath))
	return FALSE;

    for (i = 0; i < csinfo_size; i++)
    {
	if (!csinfo[i].fname)
	    continue;

	if (num == 0)
	    return TRUE;

	switch (num)
	{
	case 1:
	    if (strstr(csinfo[i].fname, (char *)dbpath))
		return TRUE;
	    break;
	case 2:
	    if (strcmp(csinfo[i].fname, (char *)dbpath) == 0)
		return TRUE;
	    break;
	case 3:
	    if (strstr(csinfo[i].fname, (char *)dbpath)
		    && ((!ppath && !csinfo[i].ppath)
			|| (ppath
			    && csinfo[i].ppath
			    && strstr(csinfo[i].ppath, (char *)ppath))))
		return TRUE;
	    break;
	case 4:
	    if ((strcmp(csinfo[i].fname, (char *)dbpath) == 0)
		    && ((!ppath && !csinfo[i].ppath)
			|| (ppath
			    && csinfo[i].ppath
			    && (strcmp(csinfo[i].ppath, (char *)ppath) == 0))))
		return TRUE;
	    break;
	}
    }

    return FALSE;
}

#endif


/*
 * PRIVATE functions
 ****************************************************************************/

/*
 * Add cscope database or a directory name (to look for cscope.out)
 * to the cscope connection list.
 */
    static int
cs_add(exarg_T *eap UNUSED)
{
    char *fname, *ppath, *flags = NULL;

    if ((fname = strtok((char *)NULL, (const char *)" ")) == NULL)
    {
	cs_usage_msg(Add);
	return CSCOPE_FAILURE;
    }
    if ((ppath = strtok((char *)NULL, (const char *)" ")) != NULL)
	flags = strtok((char *)NULL, (const char *)" ");

    return cs_add_common(fname, ppath, flags);
}

    static void
cs_stat_emsg(char *fname)
{
    int err = errno;
    (void)semsg(_(e_stat_str_error_nr), fname, err);
}


/*
 * The common routine to add a new cscope connection.  Called by
 * cs_add() and cs_reset().  I really don't like to do this, but this
 * routine uses a number of goto statements.
 */
    static int
cs_add_common(
    char *arg1,	    // filename - may contain environment variables
    char *arg2,	    // prepend path - may contain environment variables
    char *flags)
{
    stat_T	statbuf;
    int		ret;
    char	*fname = NULL;
    char	*fname2 = NULL;
    char	*ppath = NULL;
    int		i;
    int		len;
    int		usedlen = 0;
    char_u	*fbuf = NULL;

    // get the filename (arg1), expand it, and try to stat it
    if ((fname = alloc(MAXPATHL + 1)) == NULL)
	goto add_err;

    expand_env((char_u *)arg1, (char_u *)fname, MAXPATHL);
    len = (int)STRLEN(fname);
    fbuf = (char_u *)fname;
    (void)modify_fname((char_u *)":p", FALSE, &usedlen,
					      (char_u **)&fname, &fbuf, &len);
    if (fname == NULL)
	goto add_err;
    fname = (char *)vim_strnsave((char_u *)fname, len);
    vim_free(fbuf);

    ret = mch_stat(fname, &statbuf);
    if (ret < 0)
    {
staterr:
	if (p_csverbose)
	    cs_stat_emsg(fname);
	goto add_err;
    }

    // get the prepend path (arg2), expand it, and try to stat it
    if (arg2 != NULL)
    {
	stat_T	    statbuf2;

	if ((ppath = alloc(MAXPATHL + 1)) == NULL)
	    goto add_err;

	expand_env((char_u *)arg2, (char_u *)ppath, MAXPATHL);
	ret = mch_stat(ppath, &statbuf2);
	if (ret < 0)
	    goto staterr;
    }

    // if filename is a directory, append the cscope database name to it
    if (S_ISDIR(statbuf.st_mode))
    {
	fname2 = alloc(strlen(CSCOPE_DBFILE) + strlen(fname) + 2);
	if (fname2 == NULL)
	    goto add_err;

	while (fname[strlen(fname)-1] == '/'
#ifdef MSWIN
		|| fname[strlen(fname)-1] == '\\'
#endif
		)
	{
	    fname[strlen(fname)-1] = '\0';
	    if (fname[0] == '\0')
		break;
	}
	if (fname[0] == '\0')
	    (void)sprintf(fname2, "/%s", CSCOPE_DBFILE);
	else
	    (void)sprintf(fname2, "%s/%s", fname, CSCOPE_DBFILE);

	ret = mch_stat(fname2, &statbuf);
	if (ret < 0)
	{
	    if (p_csverbose)
		cs_stat_emsg(fname2);
	    goto add_err;
	}

	i = cs_insert_filelist(fname2, ppath, flags, &statbuf);
    }
    else if (S_ISREG(statbuf.st_mode) || S_ISLNK(statbuf.st_mode))
    {
	i = cs_insert_filelist(fname, ppath, flags, &statbuf);
    }
    else
    {
	if (p_csverbose)
	    (void)semsg(_(e_str_is_not_directory_or_valid_cscope_database),
									fname);
	goto add_err;
    }

    if (i != -1)
    {
	if (cs_create_connection(i) == CSCOPE_FAILURE
		|| cs_read_prompt(i) == CSCOPE_FAILURE)
	{
	    cs_release_csp(i, TRUE);
	    goto add_err;
	}

	if (p_csverbose)
	{
	    msg_clr_eos();
	    (void)smsg_attr(HL_ATTR(HLF_R),
			    _("Added cscope database %s"),
			    csinfo[i].fname);
	}
    }

    vim_free(fname);
    vim_free(fname2);
    vim_free(ppath);
    return CSCOPE_SUCCESS;

add_err:
    vim_free(fname2);
    vim_free(fname);
    vim_free(ppath);
    return CSCOPE_FAILURE;
}


    static int
cs_check_for_connections(void)
{
    return (cs_cnt_connections() > 0);
}


    static int
cs_check_for_tags(void)
{
    return (p_tags[0] != NUL && curbuf->b_p_tags != NULL);
}


/*
 * Count the number of cscope connections.
 */
    static int
cs_cnt_connections(void)
{
    int i;
    int cnt = 0;

    for (i = 0; i < csinfo_size; i++)
	if (csinfo[i].fname != NULL)
	    cnt++;
    return cnt;
}

    static void
cs_reading_emsg(
    int idx)	// connection index
{
    semsg(_(e_error_reading_cscope_connection_nr), idx);
}

#define	CSREAD_BUFSIZE	2048
/*
 * Count the number of matches for a given cscope connection.
 */
    static int
cs_cnt_matches(int idx)
{
    char *stok;
    char *buf;
    int nlines = 0;

    buf = alloc(CSREAD_BUFSIZE);
    if (buf == NULL)
	return 0;
    for (;;)
    {
	if (!fgets(buf, CSREAD_BUFSIZE, csinfo[idx].fr_fp))
	{
	    if (feof(csinfo[idx].fr_fp))
		errno = EIO;

	    cs_reading_emsg(idx);

	    vim_free(buf);
	    return -1;
	}

	/*
	 * If the database is out of date, or there's some other problem,
	 * cscope will output error messages before the number-of-lines output.
	 * Display/discard any output that doesn't match what we want.
	 * Accept "\S*cscope: X lines", also matches "mlcscope".
	 * Bail out for the "Unable to search" error.
	 */
	if (strstr((const char *)buf, "Unable to search database") != NULL)
	    break;
	if ((stok = strtok(buf, (const char *)" ")) == NULL)
	    continue;
	if (strstr((const char *)stok, "cscope:") == NULL)
	    continue;

	if ((stok = strtok(NULL, (const char *)" ")) == NULL)
	    continue;
	nlines = atoi(stok);
	if (nlines < 0)
	{
	    nlines = 0;
	    break;
	}

	if ((stok = strtok(NULL, (const char *)" ")) == NULL)
	    continue;
	if (strncmp((const char *)stok, "lines", 5))
	    continue;

	break;
    }

    vim_free(buf);
    return nlines;
}


/*
 * Creates the actual cscope command query from what the user entered.
 */
    static char *
cs_create_cmd(char *csoption, char *pattern)
{
    char *cmd;
    short search;
    char *pat;

    switch (csoption[0])
    {
    case '0' : case 's' :
	search = 0;
	break;
    case '1' : case 'g' :
	search = 1;
	break;
    case '2' : case 'd' :
	search = 2;
	break;
    case '3' : case 'c' :
	search = 3;
	break;
    case '4' : case 't' :
	search = 4;
	break;
    case '6' : case 'e' :
	search = 6;
	break;
    case '7' : case 'f' :
	search = 7;
	break;
    case '8' : case 'i' :
	search = 8;
	break;
    case '9' : case 'a' :
	search = 9;
	break;
    default :
	(void)emsg(_(e_unknown_cscope_search_type));
	cs_usage_msg(Find);
	return NULL;
    }

    // Skip white space before the pattern, except for text and pattern search,
    // they may want to use the leading white space.
    pat = pattern;
    if (search != 4 && search != 6)
	while VIM_ISWHITE(*pat)
	    ++pat;

    if ((cmd = alloc(strlen(pat) + 2)) == NULL)
	return NULL;

    (void)sprintf(cmd, "%d%s", search, pat);

    return cmd;
}


/*
 * This piece of code was taken/adapted from nvi.  do we need to add
 * the BSD license notice?
 */
    static int
cs_create_connection(int i)
{
#ifdef UNIX
    int		to_cs[2], from_cs[2];
#endif
    int		cmdlen;
    int		len;
    char	*prog, *cmd, *ppath = NULL;
#ifdef MSWIN
    int		fd;
    SECURITY_ATTRIBUTES sa;
    PROCESS_INFORMATION pi;
    STARTUPINFO si;
    BOOL	pipe_stdin = FALSE, pipe_stdout = FALSE;
    HANDLE	stdin_rd, stdout_rd;
    HANDLE	stdout_wr, stdin_wr;
    BOOL	created;
#endif

#if defined(UNIX)
    /*
     * Cscope reads from to_cs[0] and writes to from_cs[1]; vi reads from
     * from_cs[0] and writes to to_cs[1].
     */
    to_cs[0] = to_cs[1] = from_cs[0] = from_cs[1] = -1;
    if (pipe(to_cs) < 0 || pipe(from_cs) < 0)
    {
	(void)emsg(_(e_could_not_create_cscope_pipes));
err_closing:
	if (to_cs[0] != -1)
	    (void)close(to_cs[0]);
	if (to_cs[1] != -1)
	    (void)close(to_cs[1]);
	if (from_cs[0] != -1)
	    (void)close(from_cs[0]);
	if (from_cs[1] != -1)
	    (void)close(from_cs[1]);
	return CSCOPE_FAILURE;
    }

    if ((csinfo[i].pid = fork()) == -1)
    {
	(void)emsg(_(e_could_not_fork_for_cscope));
	goto err_closing;
    }
    else if (csinfo[i].pid == 0)	// child: run cscope.
    {
	char **argv = NULL;
	int argc = 0;

	if (dup2(to_cs[0], STDIN_FILENO) == -1)
	    PERROR("cs_create_connection 1");
	if (dup2(from_cs[1], STDOUT_FILENO) == -1)
	    PERROR("cs_create_connection 2");
	if (dup2(from_cs[1], STDERR_FILENO) == -1)
	    PERROR("cs_create_connection 3");

	// close unused
	(void)close(to_cs[1]);
	(void)close(from_cs[0]);
#else
	// MSWIN
	// Create pipes to communicate with cscope
	sa.nLength = sizeof(SECURITY_ATTRIBUTES);
	sa.bInheritHandle = TRUE;
	sa.lpSecurityDescriptor = NULL;

	if (!(pipe_stdin = CreatePipe(&stdin_rd, &stdin_wr, &sa, 0))
		|| !(pipe_stdout = CreatePipe(&stdout_rd, &stdout_wr, &sa, 0)))
	{
	    (void)emsg(_(e_could_not_create_cscope_pipes));
err_closing:
	    if (pipe_stdin)
	    {
		CloseHandle(stdin_rd);
		CloseHandle(stdin_wr);
	    }
	    if (pipe_stdout)
	    {
		CloseHandle(stdout_rd);
		CloseHandle(stdout_wr);
	    }
	    return CSCOPE_FAILURE;
	}
#endif
	// expand the cscope exec for env var's
	if ((prog = alloc(MAXPATHL + 1)) == NULL)
	{
#ifdef UNIX
	    exit(EXIT_FAILURE);
#else
	    // MSWIN
	    goto err_closing;
#endif
	}
	expand_env(p_csprg, (char_u *)prog, MAXPATHL);

	// alloc space to hold the cscope command
	cmdlen = (int)(strlen(prog) + strlen(csinfo[i].fname) + 32);
	if (csinfo[i].ppath)
	{
	    // expand the prepend path for env var's
	    if ((ppath = alloc(MAXPATHL + 1)) == NULL)
	    {
		vim_free(prog);
#ifdef UNIX
		exit(EXIT_FAILURE);
#else
		// MSWIN
		goto err_closing;
#endif
	    }
	    expand_env((char_u *)csinfo[i].ppath, (char_u *)ppath, MAXPATHL);

	    cmdlen += (int)strlen(ppath);
	}

	if (csinfo[i].flags)
	    cmdlen += (int)strlen(csinfo[i].flags);

	if ((cmd = alloc(cmdlen)) == NULL)
	{
	    vim_free(prog);
	    vim_free(ppath);
#ifdef UNIX
	    exit(EXIT_FAILURE);
#else
	    // MSWIN
	    goto err_closing;
#endif
	}

	// run the cscope command
#ifdef UNIX
	vim_snprintf(cmd, cmdlen, "/bin/sh -c \"exec %s -dl -f %s",
							prog, csinfo[i].fname);
#else
	vim_snprintf(cmd, cmdlen, "%s -dl -f %s", prog, csinfo[i].fname);
#endif
	if (csinfo[i].ppath != NULL)
	{
	    len = (int)STRLEN(cmd);
	    vim_snprintf(cmd + len, cmdlen - len, " -P%s", csinfo[i].ppath);
	}
	if (csinfo[i].flags != NULL)
	{
	    len = (int)STRLEN(cmd);
	    vim_snprintf(cmd + len, cmdlen - len, " %s", csinfo[i].flags);
	}
# ifdef UNIX
	// terminate the -c command argument
	STRCAT(cmd, "\"");

	// on Win32 we still need prog
	vim_free(prog);
# endif
	vim_free(ppath);

#if defined(UNIX)
# if defined(HAVE_SETSID) || defined(HAVE_SETPGID)
	// Change our process group to avoid cscope receiving SIGWINCH.
#  if defined(HAVE_SETSID)
	(void)setsid();
#  else
	if (setpgid(0, 0) == -1)
	    PERROR(_("cs_create_connection setpgid failed"));
#  endif
# endif
	if (build_argv_from_string((char_u *)cmd, &argv, &argc) == FAIL)
	    exit(EXIT_FAILURE);

	if (execvp(argv[0], argv) == -1)
	    PERROR(_("cs_create_connection exec failed"));

	exit(127);
	// NOTREACHED
    }
    else	// parent.
    {
	/*
	 * Save the file descriptors for later duplication, and
	 * reopen as streams.
	 */
	if ((csinfo[i].to_fp = fdopen(to_cs[1], "w")) == NULL)
	    PERROR(_("cs_create_connection: fdopen for to_fp failed"));
	if ((csinfo[i].fr_fp = fdopen(from_cs[0], "r")) == NULL)
	    PERROR(_("cs_create_connection: fdopen for fr_fp failed"));

	// close unused
	(void)close(to_cs[0]);
	(void)close(from_cs[1]);
    }
#else
    // MSWIN
    // Create a new process to run cscope and use pipes to talk with it
    GetStartupInfo(&si);
    si.dwFlags = STARTF_USESTDHANDLES | STARTF_USESHOWWINDOW;
    si.wShowWindow = SW_HIDE;  // Hide child application window
    si.hStdOutput = stdout_wr;
    si.hStdError  = stdout_wr;
    si.hStdInput  = stdin_rd;
    created = CreateProcess(NULL, cmd, NULL, NULL, TRUE, CREATE_NEW_CONSOLE,
							NULL, NULL, &si, &pi);
    vim_free(prog);
    vim_free(cmd);

    if (!created)
    {
	PERROR(_("cs_create_connection exec failed"));
	(void)emsg(_(e_could_not_spawn_cscope_process));
	goto err_closing;
    }
    // else
    csinfo[i].pid = pi.dwProcessId;
    csinfo[i].hProc = pi.hProcess;
    CloseHandle(pi.hThread);

    // TODO - tidy up after failure to create files on pipe handles.
    if (((fd = _open_osfhandle((intptr_t)stdin_wr,
						      _O_TEXT|_O_APPEND)) < 0)
	    || ((csinfo[i].to_fp = _fdopen(fd, "w")) == NULL))
	PERROR(_("cs_create_connection: fdopen for to_fp failed"));
    if (((fd = _open_osfhandle((intptr_t)stdout_rd,
						      _O_TEXT|_O_RDONLY)) < 0)
	    || ((csinfo[i].fr_fp = _fdopen(fd, "r")) == NULL))
	PERROR(_("cs_create_connection: fdopen for fr_fp failed"));

    // Close handles for file descriptors inherited by the cscope process
    CloseHandle(stdin_rd);
    CloseHandle(stdout_wr);

#endif // !UNIX

    return CSCOPE_SUCCESS;
}


/*
 * Query cscope using command line interface.  Parse the output and use tselect
 * to allow choices.  Like Nvi, creates a pipe to send to/from query/cscope.
 *
 * returns TRUE if we jump to a tag or abort, FALSE if not.
 */
    static int
cs_find(exarg_T *eap)
{
    char *opt, *pat;
    int i;

    if (cs_check_for_connections() == FALSE)
    {
	(void)emsg(_(e_no_cscope_connections));
	return FALSE;
    }

    if ((opt = strtok((char *)NULL, (const char *)" ")) == NULL)
    {
	cs_usage_msg(Find);
	return FALSE;
    }

    pat = opt + strlen(opt) + 1;
    if (pat >= (char *)eap->arg + eap_arg_len)
    {
	cs_usage_msg(Find);
	return FALSE;
    }

    /*
     * Let's replace the NULs written by strtok() with spaces - we need the
     * spaces to correctly display the quickfix/location list window's title.
     */
    for (i = 0; i < eap_arg_len; ++i)
	if (NUL == eap->arg[i])
	    eap->arg[i] = ' ';

    return cs_find_common(opt, pat, eap->forceit, TRUE,
				  eap->cmdidx == CMD_lcscope, *eap->cmdlinep);
}


/*
 * Common code for cscope find, shared by cs_find() and ex_cstag().
 */
    static int
cs_find_common(
    char *opt,
    char *pat,
    int forceit,
    int verbose,
    int	use_ll UNUSED,
    char_u *cmdline UNUSED)
{
    int i;
    char *cmd;
    int *nummatches;
    int totmatches;
#ifdef FEAT_QUICKFIX
    char cmdletter;
    char *qfpos;

    // get cmd letter
    switch (opt[0])
    {
    case '0' :
	cmdletter = 's';
	break;
    case '1' :
	cmdletter = 'g';
	break;
    case '2' :
	cmdletter = 'd';
	break;
    case '3' :
	cmdletter = 'c';
	break;
    case '4' :
	cmdletter = 't';
	break;
    case '6' :
	cmdletter = 'e';
	break;
    case '7' :
	cmdletter = 'f';
	break;
    case '8' :
	cmdletter = 'i';
	break;
    case '9' :
	cmdletter = 'a';
	break;
    default :
	cmdletter = opt[0];
    }

    qfpos = (char *)vim_strchr(p_csqf, cmdletter);
    if (qfpos != NULL)
    {
	qfpos++;
	// next symbol must be + or -
	if (strchr(CSQF_FLAGS, *qfpos) == NULL)
	{
	    (void)semsg(_(e_invalid_cscopequickfix_flag_chr_for_chr),
							 *qfpos, *(qfpos - 1));
	    return FALSE;
	}

	if (*qfpos != '0'
		&& apply_autocmds(EVENT_QUICKFIXCMDPRE, (char_u *)"cscope",
					       curbuf->b_fname, TRUE, curbuf))
	{
# ifdef FEAT_EVAL
	    if (aborting())
		return FALSE;
# endif
	}
    }
#endif

    // create the actual command to send to cscope
    cmd = cs_create_cmd(opt, pat);
    if (cmd == NULL)
	return FALSE;

    nummatches = ALLOC_MULT(int, csinfo_size);
    if (nummatches == NULL)
    {
	vim_free(cmd);
	return FALSE;
    }

    // Send query to all open connections, then count the total number
    // of matches so we can alloc all in one swell foop.
    for (i = 0; i < csinfo_size; i++)
	nummatches[i] = 0;
    totmatches = 0;
    for (i = 0; i < csinfo_size; i++)
    {
	if (csinfo[i].fname == NULL || csinfo[i].to_fp == NULL)
	    continue;

	// send cmd to cscope
	(void)fprintf(csinfo[i].to_fp, "%s\n", cmd);
	(void)fflush(csinfo[i].to_fp);

	nummatches[i] = cs_cnt_matches(i);

	if (nummatches[i] > -1)
	    totmatches += nummatches[i];

	if (nummatches[i] == 0)
	    (void)cs_read_prompt(i);
    }
    vim_free(cmd);

    if (totmatches == 0)
    {
	if (verbose)
	    (void)semsg(_(e_no_matches_found_for_cscope_query_str_of_str),
								     opt, pat);
	vim_free(nummatches);
	return FALSE;
    }

#ifdef FEAT_QUICKFIX
    if (qfpos != NULL && *qfpos != '0' && totmatches > 0)
    {
	// fill error list
	FILE	    *f;
	char_u	    *tmp = vim_tempname('c', TRUE);
	qf_info_T   *qi = NULL;
	win_T	    *wp = NULL;

	f = mch_fopen((char *)tmp, "w");
	if (f == NULL)
	    semsg(_(e_cant_open_file_str), tmp);
	else
	{
	    cs_file_results(f, nummatches);
	    fclose(f);
	    if (use_ll)	    // Use location list
		wp = curwin;
	    // '-' starts a new error list
	    if (qf_init(wp, tmp, (char_u *)"%f%*\\t%l%*\\t%m",
					  *qfpos == '-', cmdline, NULL) > 0)
	    {
		if (postponed_split != 0)
		{
		    (void)win_split(postponed_split > 0 ? postponed_split : 0,
						       postponed_split_flags);
		    RESET_BINDING(curwin);
		    postponed_split = 0;
		}

		apply_autocmds(EVENT_QUICKFIXCMDPOST, (char_u *)"cscope",
					       curbuf->b_fname, TRUE, curbuf);
		if (use_ll)
		    /*
		     * In the location list window, use the displayed location
		     * list. Otherwise, use the location list for the window.
		     */
		    qi = (bt_quickfix(wp->w_buffer) && wp->w_llist_ref != NULL)
			?  wp->w_llist_ref : wp->w_llist;
		qf_jump(qi, 0, 0, forceit);
	    }
	}
	mch_remove(tmp);
	vim_free(tmp);
	vim_free(nummatches);
	return TRUE;
    }
    else
#endif // FEAT_QUICKFIX
    {
	char **matches = NULL, **contexts = NULL;
	int matched = 0;

	// read output
	cs_fill_results(pat, totmatches, nummatches, &matches,
							 &contexts, &matched);
	vim_free(nummatches);
	if (matches == NULL)
	    return FALSE;

	(void)cs_manage_matches(matches, contexts, matched, Store);

	return do_tag((char_u *)pat, DT_CSCOPE, 0, forceit, verbose);
    }

}

/*
 * Print help.
 */
    static int
cs_help(exarg_T *eap UNUSED)
{
    cscmd_T *cmdp = cs_cmds;

    (void)msg_puts(_("cscope commands:\n"));
    while (cmdp->name != NULL)
    {
	char *help = _(cmdp->help);
	int  space_cnt = 30 - vim_strsize((char_u *)help);

	// Use %*s rather than %30s to ensure proper alignment in utf-8
	if (space_cnt < 0)
	    space_cnt = 0;
	(void)smsg(_("%-5s: %s%*s (Usage: %s)"),
				      cmdp->name,
				      help, space_cnt, " ",
				      cmdp->usage);
	if (strcmp(cmdp->name, "find") == 0)
	    msg_puts(_("\n"
		       "       a: Find assignments to this symbol\n"
		       "       c: Find functions calling this function\n"
		       "       d: Find functions called by this function\n"
		       "       e: Find this egrep pattern\n"
		       "       f: Find this file\n"
		       "       g: Find this definition\n"
		       "       i: Find files #including this file\n"
		       "       s: Find this C symbol\n"
		       "       t: Find this text string\n"));

	cmdp++;
    }

    wait_return(TRUE);
    return 0;
}


    static void
clear_csinfo(int i)
{
    csinfo[i].fname  = NULL;
    csinfo[i].ppath  = NULL;
    csinfo[i].flags  = NULL;
#if defined(UNIX)
    csinfo[i].st_dev = (dev_t)0;
    csinfo[i].st_ino = (ino_t)0;
#else
    csinfo[i].nVolume = 0;
    csinfo[i].nIndexHigh = 0;
    csinfo[i].nIndexLow = 0;
#endif
    csinfo[i].pid    = 0;
    csinfo[i].fr_fp  = NULL;
    csinfo[i].to_fp  = NULL;
#if defined(MSWIN)
    csinfo[i].hProc = NULL;
#endif
}

/*
 * Insert a new cscope database filename into the filelist.
 */
    static int
cs_insert_filelist(
    char *fname,
    char *ppath,
    char *flags,
    stat_T *sb UNUSED)
{
    int	    i;
    int	    j;
#ifndef UNIX
    BY_HANDLE_FILE_INFORMATION bhfi;

    switch (win32_fileinfo((char_u *)fname, &bhfi))
    {
	case FILEINFO_ENC_FAIL:		// enc_to_utf16() failed
	case FILEINFO_READ_FAIL:	// CreateFile() failed
	    if (p_csverbose)
	    {
		char *cant_msg = _(e_cannot_open_cscope_database_str);
		char *winmsg = GetWin32Error();

		if (winmsg != NULL)
		    (void)semsg(cant_msg, winmsg);
		else
		    // subst filename if can't get error text
		    (void)semsg(cant_msg, fname);
	    }
	    return -1;

	case FILEINFO_INFO_FAIL:    // GetFileInformationByHandle() failed
	    if (p_csverbose)
		(void)emsg(_(e_cannot_get_cscope_database_information));
	    return -1;
    }
#endif

    i = -1; // can be set to the index of an empty item in csinfo
    for (j = 0; j < csinfo_size; j++)
    {
	if (csinfo[j].fname != NULL
#if defined(UNIX)
	    && csinfo[j].st_dev == sb->st_dev && csinfo[j].st_ino == sb->st_ino
#else
	    // compare pathnames first
	    && ((fullpathcmp((char_u *)csinfo[j].fname,
			(char_u *)fname, FALSE, TRUE) & FPC_SAME)
		// test index file attributes too
		|| (csinfo[j].nVolume == bhfi.dwVolumeSerialNumber
		    && csinfo[j].nIndexHigh == bhfi.nFileIndexHigh
		    && csinfo[j].nIndexLow == bhfi.nFileIndexLow))
#endif
	    )
	{
	    if (p_csverbose)
		(void)emsg(_(e_duplicate_cscope_database_not_added));
	    return -1;
	}

	if (csinfo[j].fname == NULL && i == -1)
	    i = j; // remember first empty entry
    }

    if (i == -1)
    {
	i = csinfo_size;
	if (csinfo_size == 0)
	{
	    // First time allocation: allocate only 1 connection. It should
	    // be enough for most users.  If more is needed, csinfo will be
	    // reallocated.
	    csinfo_size = 1;
	    csinfo = ALLOC_CLEAR_ONE(csinfo_T);
	}
	else
	{
	    csinfo_T *t_csinfo = csinfo;

	    // Reallocate space for more connections.
	    csinfo_size *= 2;
	    csinfo = vim_realloc(csinfo, sizeof(csinfo_T)*csinfo_size);
	    if (csinfo == NULL)
	    {
		vim_free(t_csinfo);
		csinfo_size = 0;
	    }
	}
	if (csinfo == NULL)
	    return -1;
	for (j = csinfo_size/2; j < csinfo_size; j++)
	    clear_csinfo(j);
    }

    if ((csinfo[i].fname = alloc(strlen(fname)+1)) == NULL)
	return -1;

    (void)strcpy(csinfo[i].fname, (const char *)fname);

    if (ppath != NULL)
    {
	if ((csinfo[i].ppath = alloc(strlen(ppath) + 1)) == NULL)
	{
	    VIM_CLEAR(csinfo[i].fname);
	    return -1;
	}
	(void)strcpy(csinfo[i].ppath, (const char *)ppath);
    }
    else
	csinfo[i].ppath = NULL;

    if (flags != NULL)
    {
	if ((csinfo[i].flags = alloc(strlen(flags) + 1)) == NULL)
	{
	    VIM_CLEAR(csinfo[i].fname);
	    VIM_CLEAR(csinfo[i].ppath);
	    return -1;
	}
	(void)strcpy(csinfo[i].flags, (const char *)flags);
    }
    else
	csinfo[i].flags = NULL;

#if defined(UNIX)
    csinfo[i].st_dev = sb->st_dev;
    csinfo[i].st_ino = sb->st_ino;

#else
    csinfo[i].nVolume = bhfi.dwVolumeSerialNumber;
    csinfo[i].nIndexLow = bhfi.nFileIndexLow;
    csinfo[i].nIndexHigh = bhfi.nFileIndexHigh;
#endif
    return i;
}


/*
 * Find cscope command in command table.
 */
    static cscmd_T *
cs_lookup_cmd(exarg_T *eap)
{
    cscmd_T *cmdp;
    char *stok;
    size_t len;

    if (eap->arg == NULL)
	return NULL;

    // Store length of eap->arg before it gets modified by strtok().
    eap_arg_len = (int)STRLEN(eap->arg);

    if ((stok = strtok((char *)(eap->arg), (const char *)" ")) == NULL)
	return NULL;

    len = strlen(stok);
    for (cmdp = cs_cmds; cmdp->name != NULL; ++cmdp)
    {
	if (strncmp((const char *)(stok), cmdp->name, len) == 0)
	    return (cmdp);
    }
    return NULL;
}


/*
 * Nuke em.
 */
    static int
cs_kill(exarg_T *eap UNUSED)
{
    char *stok;
    int i;

    if ((stok = strtok((char *)NULL, (const char *)" ")) == NULL)
    {
	cs_usage_msg(Kill);
	return CSCOPE_FAILURE;
    }

    // only single digit positive and negative integers are allowed
    if ((strlen(stok) < 2 && VIM_ISDIGIT((int)(stok[0])))
	    || (strlen(stok) < 3 && stok[0] == '-'
					      && VIM_ISDIGIT((int)(stok[1]))))
	i = atoi(stok);
    else
    {
	// It must be part of a name.  We will try to find a match
	// within all the names in the csinfo data structure
	for (i = 0; i < csinfo_size; i++)
	{
	    if (csinfo[i].fname != NULL && strstr(csinfo[i].fname, stok))
		break;
	}
    }

    if ((i != -1) && (i >= csinfo_size || i < -1 || csinfo[i].fname == NULL))
    {
	if (p_csverbose)
	    (void)semsg(_(e_cscope_connection_str_not_founc), stok);
    }
    else
    {
	if (i == -1)
	{
	    for (i = 0; i < csinfo_size; i++)
	    {
		if (csinfo[i].fname)
		    cs_kill_execute(i, csinfo[i].fname);
	    }
	}
	else
	    cs_kill_execute(i, stok);
    }

    return 0;
}


/*
 * Actually kills a specific cscope connection.
 */
    static void
cs_kill_execute(
    int i,	    // cscope table index
    char *cname)    // cscope database name
{
    if (p_csverbose)
    {
	msg_clr_eos();
	(void)smsg_attr(HL_ATTR(HLF_R) | MSG_HIST,
			_("cscope connection %s closed"), cname);
    }
    cs_release_csp(i, TRUE);
}


/*
 * Convert the cscope output into a ctags style entry (as might be found
 * in a ctags tags file).  there's one catch though: cscope doesn't tell you
 * the type of the tag you are looking for.  for example, in Darren Hiebert's
 * ctags (the one that comes with vim), #define's use a line number to find the
 * tag in a file while function definitions use a regexp search pattern.
 *
 * I'm going to always use the line number because cscope does something
 * quirky (and probably other things i don't know about):
 *
 *     if you have "#  define" in your source file, which is
 *     perfectly legal, cscope thinks you have "#define".  this
 *     will result in a failed regexp search. :(
 *
 * Besides, even if this particular case didn't happen, the search pattern
 * would still have to be modified to escape all the special regular expression
 * characters to comply with ctags formatting.
 */
    static char *
cs_make_vim_style_matches(
    char *fname,
    char *slno,
    char *search,
    char *tagstr)
{
    // vim style is ctags:
    //
    //	    <tagstr>\t<filename>\t<linenum_or_search>"\t<extra>
    //
    // but as mentioned above, we'll always use the line number and
    // put the search pattern (if one exists) as "extra"
    //
    // buf is used as part of vim's method of handling tags, and
    // (i think) vim frees it when you pop your tags and get replaced
    // by new ones on the tag stack.
    char *buf;
    int amt;

    if (search != NULL)
    {
	amt = (int)(strlen(fname) + strlen(slno) + strlen(tagstr) + strlen(search)+6);
	if ((buf = alloc(amt)) == NULL)
	    return NULL;

	(void)sprintf(buf, "%s\t%s\t%s;\"\t%s", tagstr, fname, slno, search);
    }
    else
    {
	amt = (int)(strlen(fname) + strlen(slno) + strlen(tagstr) + 5);
	if ((buf = alloc(amt)) == NULL)
	    return NULL;

	(void)sprintf(buf, "%s\t%s\t%s;\"", tagstr, fname, slno);
    }

    return buf;
}


/*
 * This is kind of hokey, but i don't see an easy way round this.
 *
 * Store: keep a ptr to the (malloc'd) memory of matches originally
 * generated from cs_find().  the matches are originally lines directly
 * from cscope output, but transformed to look like something out of a
 * ctags.  see cs_make_vim_style_matches for more details.
 *
 * Get: used only from cs_fgets(), this simulates a vim_fgets() to return
 * the next line from the cscope output.  it basically keeps track of which
 * lines have been "used" and returns the next one.
 *
 * Free: frees up everything and resets
 *
 * Print: prints the tags
 */
    static char *
cs_manage_matches(
    char **matches,
    char **contexts,
    int totmatches,
    mcmd_e cmd)
{
    static char **mp = NULL;
    static char **cp = NULL;
    static int cnt = -1;
    static int next = -1;
    char *p = NULL;

    switch (cmd)
    {
    case Store:
	assert(matches != NULL);
	assert(totmatches > 0);
	if (mp != NULL || cp != NULL)
	    (void)cs_manage_matches(NULL, NULL, -1, Free);
	mp = matches;
	cp = contexts;
	cnt = totmatches;
	next = 0;
	break;
    case Get:
	if (next >= cnt)
	    return NULL;

	p = mp[next];
	next++;
	break;
    case Free:
	if (mp != NULL)
	{
	    if (cnt > 0)
		while (cnt--)
		{
		    vim_free(mp[cnt]);
		    if (cp != NULL)
			vim_free(cp[cnt]);
		}
	    vim_free(mp);
	    vim_free(cp);
	}
	mp = NULL;
	cp = NULL;
	cnt = 0;
	next = 0;
	break;
    case Print:
	cs_print_tags_priv(mp, cp, cnt);
	break;
    default:	// should not reach here
	iemsg(e_fatal_error_in_cs_manage_matches);
	return NULL;
    }

    return p;
}


/*
 * Parse cscope output.
 */
    static char *
cs_parse_results(
    int cnumber,
    char *buf,
    int bufsize,
    char **context,
    char **linenumber,
    char **search)
{
    int ch;
    char *p;
    char *name;

    if (fgets(buf, bufsize, csinfo[cnumber].fr_fp) == NULL)
    {
	if (feof(csinfo[cnumber].fr_fp))
	    errno = EIO;

	cs_reading_emsg(cnumber);

	return NULL;
    }

    // If the line's too long for the buffer, discard it.
    if ((p = strchr(buf, '\n')) == NULL)
    {
	while ((ch = getc(csinfo[cnumber].fr_fp)) != EOF && ch != '\n')
	    ;
	return NULL;
    }
    *p = '\0';

    /*
     * cscope output is in the following format:
     *
     *	<filename> <context> <line number> <pattern>
     */
    if ((name = strtok(buf, (const char *)" ")) == NULL)
	return NULL;
    if ((*context = strtok(NULL, (const char *)" ")) == NULL)
	return NULL;
    if ((*linenumber = strtok(NULL, (const char *)" ")) == NULL)
	return NULL;
    *search = *linenumber + strlen(*linenumber) + 1;	// +1 to skip \0

    // --- nvi ---
    // If the file is older than the cscope database, that is,
    // the database was built since the file was last modified,
    // or there wasn't a search string, use the line number.
    if (strcmp(*search, "<unknown>") == 0)
	*search = NULL;

    name = cs_resolve_file(cnumber, name);
    return name;
}

#ifdef FEAT_QUICKFIX
/*
 * Write cscope find results to file.
 */
    static void
cs_file_results(FILE *f, int *nummatches_a)
{
    int i, j;
    char *buf;
    char *search, *slno;
    char *fullname;
    char *cntx;
    char *context;

    buf = alloc(CSREAD_BUFSIZE);
    if (buf == NULL)
	return;

    for (i = 0; i < csinfo_size; i++)
    {
	if (nummatches_a[i] < 1)
	    continue;

	for (j = 0; j < nummatches_a[i]; j++)
	{
	   if ((fullname = cs_parse_results(i, buf, CSREAD_BUFSIZE, &cntx,
			   &slno, &search)) == NULL)
	       continue;

	   context = alloc(strlen(cntx)+5);
	   if (context == NULL)
	   {
	       vim_free(fullname);
	       continue;
	   }

	   if (strcmp(cntx, "<global>")==0)
	       strcpy(context, "<<global>>");
	   else
	       sprintf(context, "<<%s>>", cntx);

	   if (search == NULL)
	       fprintf(f, "%s\t%s\t%s\n", fullname, slno, context);
	   else
	       fprintf(f, "%s\t%s\t%s %s\n", fullname, slno, context, search);

	   vim_free(context);
	   vim_free(fullname);
	} // for all matches

	(void)cs_read_prompt(i);

    } // for all cscope connections
    vim_free(buf);
}
#endif

/*
 * Get parsed cscope output and calls cs_make_vim_style_matches to convert
 * into ctags format.
 * When there are no matches sets "*matches_p" to NULL.
 */
    static void
cs_fill_results(
    char *tagstr,
    int totmatches,
    int *nummatches_a,
    char ***matches_p,
    char ***cntxts_p,
    int *matched)
{
    int i, j;
    char *buf;
    char *search, *slno;
    int totsofar = 0;
    char **matches = NULL;
    char **cntxts = NULL;
    char *fullname;
    char *cntx;

    assert(totmatches > 0);

    buf = alloc(CSREAD_BUFSIZE);
    if (buf == NULL)
	return;

    if ((matches = ALLOC_MULT(char *, totmatches)) == NULL)
	goto parse_out;
    if ((cntxts = ALLOC_MULT(char *, totmatches)) == NULL)
	goto parse_out;

    for (i = 0; i < csinfo_size; i++)
    {
	if (nummatches_a[i] < 1)
	    continue;

	for (j = 0; j < nummatches_a[i]; j++)
	{
	   if ((fullname = cs_parse_results(i, buf, CSREAD_BUFSIZE, &cntx,
			   &slno, &search)) == NULL)
		continue;

	    matches[totsofar] = cs_make_vim_style_matches(fullname, slno,
							  search, tagstr);

	    vim_free(fullname);

	    if (strcmp(cntx, "<global>") == 0)
		cntxts[totsofar] = NULL;
	    else
		// note: if vim_strsave returns NULL, then the context
		// will be "<global>", which is misleading.
		cntxts[totsofar] = (char *)vim_strsave((char_u *)cntx);

	    if (matches[totsofar] != NULL)
		totsofar++;

	} // for all matches

	(void)cs_read_prompt(i);

    } // for all cscope connections

parse_out:
    if (totsofar == 0)
    {
	// No matches, free the arrays and return NULL in "*matches_p".
	VIM_CLEAR(matches);
	VIM_CLEAR(cntxts);
    }
    *matched = totsofar;
    *matches_p = matches;
    *cntxts_p = cntxts;

    vim_free(buf);
}


/*
 * get the requested path components
 */
    static char *
cs_pathcomponents(char *path)
{
    int		i;
    char	*s;

    if (p_cspc == 0)
	return path;

    s = path + strlen(path) - 1;
    for (i = 0; i < p_cspc; ++i)
	while (s > path && *--s != '/'
#ifdef MSWIN
		&& *--s != '\\'
#endif
		)
	    ;
    if ((s > path && *s == '/')
#ifdef MSWIN
	|| (s > path && *s == '\\')
#endif
	    )
	++s;
    return s;
}

/*
 * Called from cs_manage_matches().
 */
    static void
cs_print_tags_priv(char **matches, char **cntxts, int num_matches)
{
    char	*buf = NULL;
    char	*t_buf;
    int		bufsize = 0; // Track available bufsize
    int		newsize = 0;
    char	*ptag;
    char	*fname, *lno, *extra, *tbuf;
    int		i, idx, num;
    char	*globalcntx = "GLOBAL";
    char	*cntxformat = " <<%s>>";
    char	*context;
    char	*cstag_msg = _("Cscope tag: %s");
    char	*csfmt_str = "%4d %6s  ";

    assert(num_matches > 0);

    if ((tbuf = alloc(strlen(matches[0]) + 1)) == NULL)
	return;

    strcpy(tbuf, matches[0]);
    ptag = strtok(tbuf, "\t");
    if (ptag == NULL)
    {
	vim_free(tbuf);
	return;
    }

    newsize = (int)(strlen(cstag_msg) + strlen(ptag));
    buf = alloc(newsize);
    if (buf != NULL)
    {
	bufsize = newsize;
	(void)sprintf(buf, cstag_msg, ptag);
	msg_puts_attr(buf, HL_ATTR(HLF_T));
    }

    vim_free(tbuf);

    msg_puts_attr(_("\n   #   line"), HL_ATTR(HLF_T));    // strlen is 7
    msg_advance(msg_col + 2);
    msg_puts_attr(_("filename / context / line\n"), HL_ATTR(HLF_T));

    num = 1;
    for (i = 0; i < num_matches; i++)
    {
	idx = i;

	// if we really wanted to, we could avoid this malloc and strcpy
	// by parsing matches[i] on the fly and placing stuff into buf
	// directly, but that's too much of a hassle
	if ((tbuf = alloc(strlen(matches[idx]) + 1)) == NULL)
	    continue;
	(void)strcpy(tbuf, matches[idx]);

	if (strtok(tbuf, (const char *)"\t") == NULL
		|| (fname = strtok(NULL, (const char *)"\t")) == NULL
		|| (lno = strtok(NULL, (const char *)"\t")) == NULL)
	{
	    vim_free(tbuf);
	    continue;
	}
	extra = strtok(NULL, (const char *)"\t");

	lno[strlen(lno)-2] = '\0';  // ignore ;" at the end

	// hopefully 'num' (num of matches) will be less than 10^16
	newsize = (int)(strlen(csfmt_str) + 16 + strlen(lno));
	if (bufsize < newsize)
	{
	    t_buf = buf;
	    buf = vim_realloc(buf, newsize);
	    if (buf == NULL)
	    {
		bufsize = 0;
		vim_free(t_buf);
	    }
	    else
		bufsize = newsize;
	}
	if (buf != NULL)
	{
	    // csfmt_str = "%4d %6s  ";
	    (void)sprintf(buf, csfmt_str, num, lno);
	    msg_puts_attr(buf, HL_ATTR(HLF_CM));
	}
	msg_outtrans_long_attr((char_u *)cs_pathcomponents(fname),
							      HL_ATTR(HLF_CM));

	// compute the required space for the context
	if (cntxts[idx] != NULL)
	    context = cntxts[idx];
	else
	    context = globalcntx;
	newsize = (int)(strlen(context) + strlen(cntxformat));

	if (bufsize < newsize)
	{
	    t_buf = buf;
	    buf = vim_realloc(buf, newsize);
	    if (buf == NULL)
	    {
		bufsize = 0;
		vim_free(t_buf);
	    }
	    else
		bufsize = newsize;
	}
	if (buf != NULL)
	{
	    (void)sprintf(buf, cntxformat, context);

	    // print the context only if it fits on the same line
	    if (msg_col + (int)strlen(buf) >= (int)Columns)
		msg_putchar('\n');
	    msg_advance(12);
	    msg_outtrans_long_attr((char_u *)buf, 0);
	    msg_putchar('\n');
	}
	if (extra != NULL)
	{
	    msg_advance(13);
	    msg_outtrans_long_attr((char_u *)extra, 0);
	}

	vim_free(tbuf); // only after printing extra due to strtok use

	if (msg_col)
	    msg_putchar('\n');

	ui_breakcheck();
	if (got_int)
	{
	    got_int = FALSE;	// don't print any more matches
	    break;
	}

	num++;
    } // for all matches

    vim_free(buf);
}


/*
 * Read a cscope prompt (basically, skip over the ">> ").
 */
    static int
cs_read_prompt(int i)
{
    int		ch;
    char	*buf = NULL; // buffer for possible error message from cscope
    int		bufpos = 0;
    int		maxlen;
    static char *eprompt = "Press the RETURN key to continue:";
    int		epromptlen = (int)strlen(eprompt);
    int		n;

    // compute maximum allowed len for Cscope error message
    char *cs_emsg = _(e_cscope_error_str);
    maxlen = (int)(IOSIZE - strlen(cs_emsg));

    for (;;)
    {
	while ((ch = getc(csinfo[i].fr_fp)) != EOF && ch != CSCOPE_PROMPT[0])
	    // if there is room and char is printable
	    if (bufpos < maxlen - 1 && vim_isprintc(ch))
	    {
		if (buf == NULL) // lazy buffer allocation
		    buf = alloc(maxlen);
		if (buf != NULL)
		{
		    // append character to the message
		    buf[bufpos++] = ch;
		    buf[bufpos] = NUL;
		    if (bufpos >= epromptlen
			    && strcmp(&buf[bufpos - epromptlen], eprompt) == 0)
		    {
			// remove eprompt from buf
			buf[bufpos - epromptlen] = NUL;

			// print message to user
			(void)semsg(cs_emsg, buf);

			// send RETURN to cscope
			(void)putc('\n', csinfo[i].to_fp);
			(void)fflush(csinfo[i].to_fp);

			// clear buf
			bufpos = 0;
			buf[bufpos] = NUL;
		    }
		}
	    }

	for (n = 0; n < (int)strlen(CSCOPE_PROMPT); ++n)
	{
	    if (n > 0)
		ch = getc(csinfo[i].fr_fp);
	    if (ch == EOF)
	    {
		if (buf != NULL && buf[0] != NUL)
		    (void)semsg(cs_emsg, buf);
		else if (p_csverbose)
		    cs_reading_emsg(i); // don't have additional information
		cs_release_csp(i, TRUE);
		vim_free(buf);
		return CSCOPE_FAILURE;
	    }

	    if (ch != CSCOPE_PROMPT[n])
	    {
		ch = EOF;
		break;
	    }
	}

	if (ch == EOF)
	    continue;	    // didn't find the prompt
	break;		    // did find the prompt
    }

    vim_free(buf);
    return CSCOPE_SUCCESS;
}

#if defined(UNIX) && defined(SIGALRM)
/*
 * Used to catch and ignore SIGALRM below.
 */
    static void
sig_handler SIGDEFARG(sigarg)
{
    // do nothing
}
#endif

/*
 * Does the actual free'ing for the cs ptr with an optional flag of whether
 * or not to free the filename.  Called by cs_kill and cs_reset.
 */
    static void
cs_release_csp(int i, int freefnpp)
{
    /*
     * Trying to exit normally (not sure whether it is fit to UNIX cscope
     */
    if (csinfo[i].to_fp != NULL)
    {
	(void)fputs("q\n", csinfo[i].to_fp);
	(void)fflush(csinfo[i].to_fp);
    }
#if defined(UNIX)
    {
	int waitpid_errno;
	int pstat;
	pid_t pid;

# if defined(HAVE_SIGACTION)
	struct sigaction sa, old;

	// Use sigaction() to limit the waiting time to two seconds.
	sigemptyset(&sa.sa_mask);
	sa.sa_handler = sig_handler;
#  ifdef SA_NODEFER
	sa.sa_flags = SA_NODEFER;
#  else
	sa.sa_flags = 0;
#  endif
	sigaction(SIGALRM, &sa, &old);
	alarm(2); // 2 sec timeout

	// Block until cscope exits or until timer expires
	pid = waitpid(csinfo[i].pid, &pstat, 0);
	waitpid_errno = errno;

	// cancel pending alarm if still there and restore signal
	alarm(0);
	sigaction(SIGALRM, &old, NULL);
# else
	int waited;

	// Can't use sigaction(), loop for two seconds.  First yield the CPU
	// to give cscope a chance to exit quickly.
	sleep(0);
	for (waited = 0; waited < 40; ++waited)
	{
	    pid = waitpid(csinfo[i].pid, &pstat, WNOHANG);
	    waitpid_errno = errno;
	    if (pid != 0)
		break;  // break unless the process is still running
	    mch_delay(50L, 0); // sleep 50 ms
	}
# endif
	/*
	 * If the cscope process is still running: kill it.
	 * Safety check: If the PID would be zero here, the entire X session
	 * would be killed.  -1 and 1 are dangerous as well.
	 */
	if (pid < 0 && csinfo[i].pid > 1)
	{
# ifdef ECHILD
	    int alive = TRUE;

	    if (waitpid_errno == ECHILD)
	    {
		/*
		 * When using 'vim -g', vim is forked and cscope process is
		 * no longer a child process but a sibling.  So waitpid()
		 * fails with errno being ECHILD (No child processes).
		 * Don't send SIGKILL to cscope immediately but wait
		 * (polling) for it to exit normally as result of sending
		 * the "q" command, hence giving it a chance to clean up
		 * its temporary files.
		 */
		int waited;

		sleep(0);
		for (waited = 0; waited < 40; ++waited)
		{
		    // Check whether cscope process is still alive
		    if (kill(csinfo[i].pid, 0) != 0)
		    {
			alive = FALSE; // cscope process no longer exists
			break;
		    }
		    mch_delay(50L, 0); // sleep 50 ms
		}
	    }
	    if (alive)
# endif
	    {
		kill(csinfo[i].pid, SIGKILL);
		(void)waitpid(csinfo[i].pid, &pstat, 0);
	    }
	}
    }
#else  // !UNIX
    if (csinfo[i].hProc != NULL)
    {
	// Give cscope a chance to exit normally
	if (WaitForSingleObject(csinfo[i].hProc, 1000) == WAIT_TIMEOUT)
	    TerminateProcess(csinfo[i].hProc, 0);
	CloseHandle(csinfo[i].hProc);
    }
#endif

    if (csinfo[i].fr_fp != NULL)
	(void)fclose(csinfo[i].fr_fp);
    if (csinfo[i].to_fp != NULL)
	(void)fclose(csinfo[i].to_fp);

    if (freefnpp)
    {
	vim_free(csinfo[i].fname);
	vim_free(csinfo[i].ppath);
	vim_free(csinfo[i].flags);
    }

    clear_csinfo(i);
}


/*
 * Calls cs_kill on all cscope connections then reinits.
 */
    static int
cs_reset(exarg_T *eap UNUSED)
{
    char	**dblist = NULL, **pplist = NULL, **fllist = NULL;
    int	i;
    char buf[20]; // for sprintf " (#%d)"

    if (csinfo_size == 0)
	return CSCOPE_SUCCESS;

    // malloc our db and ppath list
    dblist = ALLOC_MULT(char *, csinfo_size);
    pplist = ALLOC_MULT(char *, csinfo_size);
    fllist = ALLOC_MULT(char *, csinfo_size);
    if (dblist == NULL || pplist == NULL || fllist == NULL)
    {
	vim_free(dblist);
	vim_free(pplist);
	vim_free(fllist);
	return CSCOPE_FAILURE;
    }

    for (i = 0; i < csinfo_size; i++)
    {
	dblist[i] = csinfo[i].fname;
	pplist[i] = csinfo[i].ppath;
	fllist[i] = csinfo[i].flags;
	if (csinfo[i].fname != NULL)
	    cs_release_csp(i, FALSE);
    }

    // rebuild the cscope connection list
    for (i = 0; i < csinfo_size; i++)
    {
	if (dblist[i] != NULL)
	{
	    cs_add_common(dblist[i], pplist[i], fllist[i]);
	    if (p_csverbose)
	    {
		// don't use smsg_attr() because we want to display the
		// connection number in the same line as
		// "Added cscope database..."
		sprintf(buf, " (#%d)", i);
		msg_puts_attr(buf, HL_ATTR(HLF_R));
	    }
	}
	vim_free(dblist[i]);
	vim_free(pplist[i]);
	vim_free(fllist[i]);
    }
    vim_free(dblist);
    vim_free(pplist);
    vim_free(fllist);

    if (p_csverbose)
	msg_attr(_("All cscope databases reset"), HL_ATTR(HLF_R) | MSG_HIST);
    return CSCOPE_SUCCESS;
}


/*
 * Construct the full pathname to a file found in the cscope database.
 * (Prepends ppath, if there is one and if it's not already prepended,
 * otherwise just uses the name found.)
 *
 * We need to prepend the prefix because on some cscope's (e.g., the one that
 * ships with Solaris 2.6), the output never has the prefix prepended.
 * Contrast this with my development system (Digital Unix), which does.
 */
    static char *
cs_resolve_file(int i, char *name)
{
    char	*fullname;
    int		len;
    char_u	*csdir = NULL;

    /*
     * Ppath is freed when we destroy the cscope connection.
     * Fullname is freed after cs_make_vim_style_matches, after it's been
     * copied into the tag buffer used by Vim.
     */
    len = (int)(strlen(name) + 2);
    if (csinfo[i].ppath != NULL)
	len += (int)strlen(csinfo[i].ppath);
    else if (p_csre && csinfo[i].fname != NULL)
    {
	// If 'cscoperelative' is set and ppath is not set, use cscope.out
	// path in path resolution.
	csdir = alloc(MAXPATHL);
	if (csdir != NULL)
	{
	    vim_strncpy(csdir, (char_u *)csinfo[i].fname,
					  gettail((char_u *)csinfo[i].fname)
						 - (char_u *)csinfo[i].fname);
	    len += (int)STRLEN(csdir);
	}
    }

    // Note/example: this won't work if the cscope output already starts
    // "../.." and the prefix path is also "../..".  if something like this
    // happens, you are screwed up and need to fix how you're using cscope.
    if (csinfo[i].ppath != NULL
	    && (strncmp(name, csinfo[i].ppath, strlen(csinfo[i].ppath)) != 0)
	    && (name[0] != '/')
#ifdef MSWIN
	    && name[0] != '\\' && name[1] != ':'
#endif
       )
    {
	if ((fullname = alloc(len)) != NULL)
	    (void)sprintf(fullname, "%s/%s", csinfo[i].ppath, name);
    }
    else if (csdir != NULL && csinfo[i].fname != NULL && *csdir != NUL)
    {
	// Check for csdir to be non empty to avoid empty path concatenated to
	// cscope output.
	fullname = (char *)concat_fnames(csdir, (char_u *)name, TRUE);
    }
    else
    {
	fullname = (char *)vim_strsave((char_u *)name);
    }

    vim_free(csdir);
    return fullname;
}


/*
 * Show all cscope connections.
 */
    static int
cs_show(exarg_T *eap UNUSED)
{
    int i;

    if (cs_cnt_connections() == 0)
	msg_puts(_("no cscope connections\n"));
    else
    {
	msg_puts_attr(
	    _(" # pid    database name                       prepend path\n"),
	    HL_ATTR(HLF_T));
	for (i = 0; i < csinfo_size; i++)
	{
	    if (csinfo[i].fname == NULL)
		continue;

	    if (csinfo[i].ppath != NULL)
		(void)smsg("%2d %-5ld  %-34s  %-32s",
		    i, (long)csinfo[i].pid, csinfo[i].fname, csinfo[i].ppath);
	    else
		(void)smsg("%2d %-5ld  %-34s  <none>",
			   i, (long)csinfo[i].pid, csinfo[i].fname);
	}
    }

    wait_return(FALSE);
    return CSCOPE_SUCCESS;
}


/*
 * Only called when VIM exits to quit any cscope sessions.
 */
    void
cs_end(void)
{
    int i;

    for (i = 0; i < csinfo_size; i++)
	cs_release_csp(i, TRUE);
    vim_free(csinfo);
    csinfo_size = 0;
}

#endif	// FEAT_CSCOPE

#if defined(FEAT_EVAL) || defined(PROTO)

/*
 * "cscope_connection([{num} , {dbpath} [, {prepend}]])" function
 *
 * Checks the existence of a cscope connection.
 */
    void
f_cscope_connection(typval_T *argvars UNUSED, typval_T *rettv UNUSED)
{
# ifdef FEAT_CSCOPE
    int		num = 0;
    char_u	*dbpath = NULL;
    char_u	*prepend = NULL;
    char_u	buf[NUMBUFLEN];

    if (in_vim9script()
	    && (check_for_opt_number_arg(argvars, 0) == FAIL
		|| (argvars[0].v_type != VAR_UNKNOWN
		    && (check_for_opt_string_arg(argvars, 1) == FAIL
			|| (argvars[1].v_type != VAR_UNKNOWN
			    && check_for_opt_string_arg(argvars, 2) == FAIL)))))
	return;

    if (argvars[0].v_type != VAR_UNKNOWN
	    && argvars[1].v_type != VAR_UNKNOWN)
    {
	num = (int)tv_get_number(&argvars[0]);
	dbpath = tv_get_string(&argvars[1]);
	if (argvars[2].v_type != VAR_UNKNOWN)
	    prepend = tv_get_string_buf(&argvars[2], buf);
    }

    rettv->vval.v_number = cs_connection(num, dbpath, prepend);
# endif
}

#endif // FEAT_EVAL