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freebsd-skq/contrib/nvi/ex/ex_argv.c

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/*-
* Copyright (c) 1993, 1994
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1993, 1994, 1995, 1996
* Keith Bostic. All rights reserved.
*
* See the LICENSE file for redistribution information.
*/
#include "config.h"
#ifndef lint
static const char sccsid[] = "$Id: ex_argv.c,v 11.2 2012/10/09 23:00:29 zy Exp $";
#endif /* not lint */
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/time.h>
#include <bitstring.h>
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <limits.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "../common/common.h"
static int argv_alloc(SCR *, size_t);
static int argv_comp(const void *, const void *);
static int argv_fexp(SCR *, EXCMD *,
CHAR_T *, size_t, CHAR_T *, size_t *, CHAR_T **, size_t *, int);
static int argv_sexp(SCR *, CHAR_T **, size_t *, size_t *);
static int argv_flt_user(SCR *, EXCMD *, CHAR_T *, size_t);
/*
* argv_init --
* Build a prototype arguments list.
*
* PUBLIC: int argv_init(SCR *, EXCMD *);
*/
int
argv_init(SCR *sp, EXCMD *excp)
{
EX_PRIVATE *exp;
exp = EXP(sp);
exp->argsoff = 0;
argv_alloc(sp, 1);
excp->argv = exp->args;
excp->argc = exp->argsoff;
return (0);
}
/*
* argv_exp0 --
* Append a string to the argument list.
*
* PUBLIC: int argv_exp0(SCR *, EXCMD *, CHAR_T *, size_t);
*/
int
argv_exp0(SCR *sp, EXCMD *excp, CHAR_T *cmd, size_t cmdlen)
{
EX_PRIVATE *exp;
exp = EXP(sp);
argv_alloc(sp, cmdlen);
MEMCPY(exp->args[exp->argsoff]->bp, cmd, cmdlen);
exp->args[exp->argsoff]->bp[cmdlen] = '\0';
exp->args[exp->argsoff]->len = cmdlen;
++exp->argsoff;
excp->argv = exp->args;
excp->argc = exp->argsoff;
return (0);
}
/*
* argv_exp1 --
* Do file name expansion on a string, and append it to the
* argument list.
*
* PUBLIC: int argv_exp1(SCR *, EXCMD *, CHAR_T *, size_t, int);
*/
int
argv_exp1(SCR *sp, EXCMD *excp, CHAR_T *cmd, size_t cmdlen, int is_bang)
{
EX_PRIVATE *exp;
size_t blen, len;
CHAR_T *p, *t, *bp;
GET_SPACE_RETW(sp, bp, blen, 512);
len = 0;
exp = EXP(sp);
if (argv_fexp(sp, excp, cmd, cmdlen, bp, &len, &bp, &blen, is_bang)) {
FREE_SPACEW(sp, bp, blen);
return (1);
}
/* If it's empty, we're done. */
if (len != 0) {
for (p = bp, t = bp + len; p < t; ++p)
if (!cmdskip(*p))
break;
if (p == t)
goto ret;
} else
goto ret;
(void)argv_exp0(sp, excp, bp, len);
ret: FREE_SPACEW(sp, bp, blen);
return (0);
}
/*
* argv_exp2 --
* Do file name and shell expansion on a string, and append it to
* the argument list.
*
* PUBLIC: int argv_exp2(SCR *, EXCMD *, CHAR_T *, size_t);
*/
int
argv_exp2(SCR *sp, EXCMD *excp, CHAR_T *cmd, size_t cmdlen)
{
size_t blen, len, n;
int rval;
CHAR_T *bp, *p;
GET_SPACE_RETW(sp, bp, blen, 512);
#define SHELLECHO L("echo ")
#define SHELLOFFSET (SIZE(SHELLECHO) - 1)
MEMCPY(bp, SHELLECHO, SHELLOFFSET);
p = bp + SHELLOFFSET;
len = SHELLOFFSET;
#if defined(DEBUG) && 0
TRACE(sp, "file_argv: {%.*s}\n", (int)cmdlen, cmd);
#endif
if (argv_fexp(sp, excp, cmd, cmdlen, p, &len, &bp, &blen, 0)) {
rval = 1;
goto err;
}
#if defined(DEBUG) && 0
TRACE(sp, "before shell: %d: {%s}\n", len, bp);
#endif
/*
* Do shell word expansion -- it's very, very hard to figure out what
* magic characters the user's shell expects. Historically, it was a
* union of v7 shell and csh meta characters. We match that practice
* by default, so ":read \%" tries to read a file named '%'. It would
* make more sense to pass any special characters through the shell,
* but then, if your shell was csh, the above example will behave
* differently in nvi than in vi. If you want to get other characters
* passed through to your shell, change the "meta" option.
*/
if (opts_empty(sp, O_SHELL, 1) || opts_empty(sp, O_SHELLMETA, 1))
n = 0;
else {
p = bp + SHELLOFFSET;
n = len - SHELLOFFSET;
for (; n > 0; --n, ++p)
if (IS_SHELLMETA(sp, *p))
break;
}
/*
* If we found a meta character in the string, fork a shell to expand
* it. Unfortunately, this is comparatively slow. Historically, it
* didn't matter much, since users don't enter meta characters as part
* of pathnames that frequently. The addition of filename completion
* broke that assumption because it's easy to use. To increase the
* completion performance, nvi used to have an internal routine to
* handle "filename*". However, the shell special characters does not
* limit to "shellmeta", so such a hack breaks historic practice.
* After it all, we split the completion logic out from here.
*/
switch (n) {
case 0:
p = bp + SHELLOFFSET;
len -= SHELLOFFSET;
rval = argv_exp3(sp, excp, p, len);
break;
default:
if (argv_sexp(sp, &bp, &blen, &len)) {
rval = 1;
goto err;
}
p = bp;
rval = argv_exp3(sp, excp, p, len);
break;
}
err: FREE_SPACEW(sp, bp, blen);
return (rval);
}
/*
* argv_exp3 --
* Take a string and break it up into an argv, which is appended
* to the argument list.
*
* PUBLIC: int argv_exp3(SCR *, EXCMD *, CHAR_T *, size_t);
*/
int
argv_exp3(SCR *sp, EXCMD *excp, CHAR_T *cmd, size_t cmdlen)
{
EX_PRIVATE *exp;
size_t len;
int ch, off;
CHAR_T *ap, *p;
for (exp = EXP(sp); cmdlen > 0; ++exp->argsoff) {
/* Skip any leading whitespace. */
for (; cmdlen > 0; --cmdlen, ++cmd) {
ch = *cmd;
if (!cmdskip(ch))
break;
}
if (cmdlen == 0)
break;
/*
* Determine the length of this whitespace delimited
* argument.
*
* QUOTING NOTE:
*
* Skip any character preceded by the user's quoting
* character.
*/
for (ap = cmd, len = 0; cmdlen > 0; ++cmd, --cmdlen, ++len) {
ch = *cmd;
if (IS_ESCAPE(sp, excp, ch) && cmdlen > 1) {
++cmd;
--cmdlen;
} else if (cmdskip(ch))
break;
}
/*
* Copy the argument into place.
*
* QUOTING NOTE:
*
* Lose quote chars.
*/
argv_alloc(sp, len);
off = exp->argsoff;
exp->args[off]->len = len;
for (p = exp->args[off]->bp; len > 0; --len, *p++ = *ap++)
if (IS_ESCAPE(sp, excp, *ap))
++ap;
*p = '\0';
}
excp->argv = exp->args;
excp->argc = exp->argsoff;
#if defined(DEBUG) && 0
for (cnt = 0; cnt < exp->argsoff; ++cnt)
TRACE(sp, "arg %d: {%s}\n", cnt, exp->argv[cnt]);
#endif
return (0);
}
/*
* argv_flt_ex --
* Filter the ex commands with a prefix, and append the results to
* the argument list.
*
* PUBLIC: int argv_flt_ex(SCR *, EXCMD *, CHAR_T *, size_t);
*/
int
argv_flt_ex(SCR *sp, EXCMD *excp, CHAR_T *cmd, size_t cmdlen)
{
EX_PRIVATE *exp;
EXCMDLIST const *cp;
int off;
size_t len;
exp = EXP(sp);
for (off = exp->argsoff, cp = cmds; cp->name != NULL; ++cp) {
len = STRLEN(cp->name);
if (cmdlen > 0 &&
(cmdlen > len || MEMCMP(cmd, cp->name, cmdlen)))
continue;
/* Copy the matched ex command name. */
argv_alloc(sp, len + 1);
MEMCPY(exp->args[exp->argsoff]->bp, cp->name, len + 1);
exp->args[exp->argsoff]->len = len;
++exp->argsoff;
excp->argv = exp->args;
excp->argc = exp->argsoff;
}
return (0);
}
/*
* argv_flt_user --
* Filter the ~user list on the system with a prefix, and append
* the results to the argument list.
*/
static int
argv_flt_user(SCR *sp, EXCMD *excp, CHAR_T *uname, size_t ulen)
{
EX_PRIVATE *exp;
struct passwd *pw;
int off;
char *np;
size_t len, nlen;
exp = EXP(sp);
off = exp->argsoff;
/* The input must come with a leading '~'. */
INT2CHAR(sp, uname + 1, ulen - 1, np, nlen);
if ((np = v_strdup(sp, np, nlen)) == NULL)
return (1);
setpwent();
while ((pw = getpwent()) != NULL) {
len = strlen(pw->pw_name);
if (nlen > 0 &&
(nlen > len || memcmp(np, pw->pw_name, nlen)))
continue;
/* Copy '~' + the matched user name. */
CHAR2INT(sp, pw->pw_name, len + 1, uname, ulen);
argv_alloc(sp, ulen + 1);
exp->args[exp->argsoff]->bp[0] = '~';
MEMCPY(exp->args[exp->argsoff]->bp + 1, uname, ulen);
exp->args[exp->argsoff]->len = ulen;
++exp->argsoff;
excp->argv = exp->args;
excp->argc = exp->argsoff;
}
endpwent();
free(np);
qsort(exp->args + off, exp->argsoff - off, sizeof(ARGS *), argv_comp);
return (0);
}
/*
* argv_fexp --
* Do file name and bang command expansion.
*/
static int
argv_fexp(SCR *sp, EXCMD *excp, CHAR_T *cmd, size_t cmdlen, CHAR_T *p, size_t *lenp, CHAR_T **bpp, size_t *blenp, int is_bang)
{
EX_PRIVATE *exp;
char *t;
size_t blen, len, off, tlen;
CHAR_T *bp;
CHAR_T *wp;
size_t wlen;
/* Replace file name characters. */
for (bp = *bpp, blen = *blenp, len = *lenp; cmdlen > 0; --cmdlen, ++cmd)
switch (*cmd) {
case '!':
if (!is_bang)
goto ins_ch;
exp = EXP(sp);
if (exp->lastbcomm == NULL) {
msgq(sp, M_ERR,
"115|No previous command to replace \"!\"");
return (1);
}
len += tlen = STRLEN(exp->lastbcomm);
off = p - bp;
ADD_SPACE_RETW(sp, bp, blen, len);
p = bp + off;
MEMCPY(p, exp->lastbcomm, tlen);
p += tlen;
F_SET(excp, E_MODIFY);
break;
case '%':
if ((t = sp->frp->name) == NULL) {
msgq(sp, M_ERR,
"116|No filename to substitute for %%");
return (1);
}
tlen = strlen(t);
len += tlen;
off = p - bp;
ADD_SPACE_RETW(sp, bp, blen, len);
p = bp + off;
CHAR2INT(sp, t, tlen, wp, wlen);
MEMCPY(p, wp, wlen);
p += wlen;
F_SET(excp, E_MODIFY);
break;
case '#':
if ((t = sp->alt_name) == NULL) {
msgq(sp, M_ERR,
"117|No filename to substitute for #");
return (1);
}
len += tlen = strlen(t);
off = p - bp;
ADD_SPACE_RETW(sp, bp, blen, len);
p = bp + off;
CHAR2INT(sp, t, tlen, wp, wlen);
MEMCPY(p, wp, wlen);
p += wlen;
F_SET(excp, E_MODIFY);
break;
case '\\':
/*
* QUOTING NOTE:
*
* Strip any backslashes that protected the file
* expansion characters.
*/
if (cmdlen > 1 &&
(cmd[1] == '%' || cmd[1] == '#' || cmd[1] == '!')) {
++cmd;
--cmdlen;
}
/* FALLTHROUGH */
default:
ins_ch: ++len;
off = p - bp;
ADD_SPACE_RETW(sp, bp, blen, len);
p = bp + off;
*p++ = *cmd;
}
/* Nul termination. */
++len;
off = p - bp;
ADD_SPACE_RETW(sp, bp, blen, len);
p = bp + off;
*p = '\0';
/* Return the new string length, buffer, buffer length. */
*lenp = len - 1;
*bpp = bp;
*blenp = blen;
return (0);
}
/*
* argv_alloc --
* Make more space for arguments.
*/
static int
argv_alloc(SCR *sp, size_t len)
{
ARGS *ap;
EX_PRIVATE *exp;
int cnt, off;
/*
* Allocate room for another argument, always leaving
* enough room for an ARGS structure with a length of 0.
*/
#define INCREMENT 20
exp = EXP(sp);
off = exp->argsoff;
if (exp->argscnt == 0 || off + 2 >= exp->argscnt - 1) {
cnt = exp->argscnt + INCREMENT;
REALLOC(sp, exp->args, ARGS **, cnt * sizeof(ARGS *));
if (exp->args == NULL) {
(void)argv_free(sp);
goto mem;
}
memset(&exp->args[exp->argscnt], 0, INCREMENT * sizeof(ARGS *));
exp->argscnt = cnt;
}
/* First argument. */
if (exp->args[off] == NULL) {
CALLOC(sp, exp->args[off], ARGS *, 1, sizeof(ARGS));
if (exp->args[off] == NULL)
goto mem;
}
/* First argument buffer. */
ap = exp->args[off];
ap->len = 0;
if (ap->blen < len + 1) {
ap->blen = len + 1;
REALLOC(sp, ap->bp, CHAR_T *, ap->blen * sizeof(CHAR_T));
if (ap->bp == NULL) {
ap->bp = NULL;
ap->blen = 0;
F_CLR(ap, A_ALLOCATED);
mem: msgq(sp, M_SYSERR, NULL);
return (1);
}
F_SET(ap, A_ALLOCATED);
}
/* Second argument. */
if (exp->args[++off] == NULL) {
CALLOC(sp, exp->args[off], ARGS *, 1, sizeof(ARGS));
if (exp->args[off] == NULL)
goto mem;
}
/* 0 length serves as end-of-argument marker. */
exp->args[off]->len = 0;
return (0);
}
/*
* argv_free --
* Free up argument structures.
*
* PUBLIC: int argv_free(SCR *);
*/
int
argv_free(SCR *sp)
{
EX_PRIVATE *exp;
int off;
exp = EXP(sp);
if (exp->args != NULL) {
for (off = 0; off < exp->argscnt; ++off) {
if (exp->args[off] == NULL)
continue;
if (F_ISSET(exp->args[off], A_ALLOCATED))
free(exp->args[off]->bp);
free(exp->args[off]);
}
free(exp->args);
}
exp->args = NULL;
exp->argscnt = 0;
exp->argsoff = 0;
return (0);
}
/*
* argv_flt_path --
* Find all file names matching the prefix and append them to the
* argument list.
*
* PUBLIC: int argv_flt_path(SCR *, EXCMD *, CHAR_T *, size_t);
*/
int
argv_flt_path(SCR *sp, EXCMD *excp, CHAR_T *path, size_t plen)
{
struct dirent *dp;
DIR *dirp;
EX_PRIVATE *exp;
int off;
size_t dlen, len, nlen;
CHAR_T *dname;
CHAR_T *p, *np, *n;
char *name, *tp, *epd = NULL;
CHAR_T *wp;
size_t wlen;
exp = EXP(sp);
/* Set up the name and length for comparison. */
if ((path = v_wstrdup(sp, path, plen)) == NULL)
return (1);
if ((p = STRRCHR(path, '/')) == NULL) {
if (*path == '~') {
int rc;
/* Filter ~user list instead. */
rc = argv_flt_user(sp, excp, path, plen);
free(path);
return (rc);
}
dname = L(".");
dlen = 0;
np = path;
} else {
if (p == path) {
dname = L("/");
dlen = 1;
} else {
*p = '\0';
dname = path;
dlen = p - path;
}
np = p + 1;
}
INT2CHAR(sp, dname, dlen + 1, tp, nlen);
if ((epd = expanduser(tp)) != NULL)
tp = epd;
if ((dirp = opendir(tp)) == NULL) {
free(epd);
free(path);
return (1);
}
free(epd);
INT2CHAR(sp, np, STRLEN(np), tp, nlen);
if ((name = v_strdup(sp, tp, nlen)) == NULL) {
free(path);
return (1);
}
for (off = exp->argsoff; (dp = readdir(dirp)) != NULL;) {
if (nlen == 0) {
if (dp->d_name[0] == '.')
continue;
len = dp->d_namlen;
} else {
len = dp->d_namlen;
if (len < nlen || memcmp(dp->d_name, name, nlen))
continue;
}
/* Directory + name + slash + null. */
CHAR2INT(sp, dp->d_name, len + 1, wp, wlen);
argv_alloc(sp, dlen + wlen + 1);
n = exp->args[exp->argsoff]->bp;
if (dlen != 0) {
MEMCPY(n, dname, dlen);
n += dlen;
if (dlen > 1 || dname[0] != '/')
*n++ = '/';
exp->args[exp->argsoff]->len = dlen + 1;
}
MEMCPY(n, wp, wlen);
exp->args[exp->argsoff]->len += wlen - 1;
++exp->argsoff;
excp->argv = exp->args;
excp->argc = exp->argsoff;
}
closedir(dirp);
free(name);
free(path);
qsort(exp->args + off, exp->argsoff - off, sizeof(ARGS *), argv_comp);
return (0);
}
/*
* argv_comp --
* Alphabetic comparison.
*/
static int
argv_comp(const void *a, const void *b)
{
return (STRCMP((*(ARGS **)a)->bp, (*(ARGS **)b)->bp));
}
/*
* argv_sexp --
* Fork a shell, pipe a command through it, and read the output into
* a buffer.
*/
static int
argv_sexp(SCR *sp, CHAR_T **bpp, size_t *blenp, size_t *lenp)
{
enum { SEXP_ERR, SEXP_EXPANSION_ERR, SEXP_OK } rval;
FILE *ifp;
pid_t pid;
size_t blen, len;
int ch, std_output[2];
CHAR_T *bp, *p;
char *sh, *sh_path;
char *np;
size_t nlen;
/* Secure means no shell access. */
if (O_ISSET(sp, O_SECURE)) {
msgq(sp, M_ERR,
"289|Shell expansions not supported when the secure edit option is set");
return (1);
}
sh_path = O_STR(sp, O_SHELL);
if ((sh = strrchr(sh_path, '/')) == NULL)
sh = sh_path;
else
++sh;
/* Local copies of the buffer variables. */
bp = *bpp;
blen = *blenp;
/*
* There are two different processes running through this code, named
* the utility (the shell) and the parent. The utility reads standard
* input and writes standard output and standard error output. The
* parent writes to the utility, reads its standard output and ignores
* its standard error output. Historically, the standard error output
* was discarded by vi, as it produces a lot of noise when file patterns
* don't match.
*
* The parent reads std_output[0], and the utility writes std_output[1].
*/
ifp = NULL;
std_output[0] = std_output[1] = -1;
if (pipe(std_output) < 0) {
msgq(sp, M_SYSERR, "pipe");
return (1);
}
if ((ifp = fdopen(std_output[0], "r")) == NULL) {
msgq(sp, M_SYSERR, "fdopen");
goto err;
}
/*
* Do the minimal amount of work possible, the shell is going to run
* briefly and then exit. We sincerely hope.
*/
switch (pid = vfork()) {
case -1: /* Error. */
msgq(sp, M_SYSERR, "vfork");
err: if (ifp != NULL)
(void)fclose(ifp);
else if (std_output[0] != -1)
close(std_output[0]);
if (std_output[1] != -1)
close(std_output[0]);
return (1);
case 0: /* Utility. */
/* Redirect stdout to the write end of the pipe. */
(void)dup2(std_output[1], STDOUT_FILENO);
/* Close the utility's file descriptors. */
(void)close(std_output[0]);
(void)close(std_output[1]);
(void)close(STDERR_FILENO);
/*
* XXX
* Assume that all shells have -c.
*/
INT2CHAR(sp, bp, STRLEN(bp)+1, np, nlen);
execl(sh_path, sh, "-c", np, (char *)NULL);
msgq_str(sp, M_SYSERR, sh_path, "118|Error: execl: %s");
_exit(127);
default: /* Parent. */
/* Close the pipe ends the parent won't use. */
(void)close(std_output[1]);
break;
}
/*
* Copy process standard output into a buffer.
*
* !!!
* Historic vi apparently discarded leading \n and \r's from
* the shell output stream. We don't on the grounds that any
* shell that does that is broken.
*/
for (p = bp, len = 0, ch = EOF;
(ch = GETC(ifp)) != EOF; *p++ = ch, blen-=sizeof(CHAR_T), ++len)
if (blen < 5) {
ADD_SPACE_GOTOW(sp, bp, *blenp, *blenp * 2);
p = bp + len;
blen = *blenp - len;
}
/* Delete the final newline, nul terminate the string. */
if (p > bp && (p[-1] == '\n' || p[-1] == '\r')) {
--p;
--len;
}
*p = '\0';
*lenp = len;
*bpp = bp; /* *blenp is already updated. */
if (ferror(ifp))
goto ioerr;
if (fclose(ifp)) {
ioerr: msgq_str(sp, M_ERR, sh, "119|I/O error: %s");
alloc_err: rval = SEXP_ERR;
} else
rval = SEXP_OK;
/*
* Wait for the process. If the shell process fails (e.g., "echo $q"
* where q wasn't a defined variable) or if the returned string has
* no characters or only blank characters, (e.g., "echo $5"), complain
* that the shell expansion failed. We can't know for certain that's
* the error, but it's a good guess, and it matches historic practice.
* This won't catch "echo foo_$5", but that's not a common error and
* historic vi didn't catch it either.
*/
if (proc_wait(sp, (long)pid, sh, 1, 0))
rval = SEXP_EXPANSION_ERR;
for (p = bp; len; ++p, --len)
if (!cmdskip(*p))
break;
if (len == 0)
rval = SEXP_EXPANSION_ERR;
if (rval == SEXP_EXPANSION_ERR)
msgq(sp, M_ERR, "304|Shell expansion failed");
return (rval == SEXP_OK ? 0 : 1);
}
/*
* argv_esc --
* Escape a string into an ex and shell argument.
*
* PUBLIC: CHAR_T *argv_esc(SCR *, EXCMD *, CHAR_T *, size_t);
*/
CHAR_T *
argv_esc(SCR *sp, EXCMD *excp, CHAR_T *str, size_t len)
{
size_t blen, off;
CHAR_T *bp, *p;
int ch;
GET_SPACE_GOTOW(sp, bp, blen, len + 1);
/*
* Leaving the first '~' unescaped causes the user to need a
* "./" prefix to edit a file which really starts with a '~'.
* However, the file completion happens to not work for these
* files without the prefix.
*
* All ex expansion characters, "!%#", are double escaped.
*/
for (p = bp; len > 0; ++str, --len) {
ch = *str;
off = p - bp;
if (blen / sizeof(CHAR_T) - off < 3) {
ADD_SPACE_GOTOW(sp, bp, blen, off + 3);
p = bp + off;
}
if (cmdskip(ch) || ch == '\n' ||
IS_ESCAPE(sp, excp, ch)) /* Ex. */
*p++ = CH_LITERAL;
else switch (ch) {
case '~': /* ~user. */
if (p != bp)
*p++ = '\\';
break;
case '+': /* Ex +cmd. */
if (p == bp)
*p++ = '\\';
break;
case '!': case '%': case '#': /* Ex exp. */
*p++ = '\\';
*p++ = '\\';
break;
case ',': case '-': case '.': case '/': /* Safe. */
case ':': case '=': case '@': case '_':
break;
default: /* Unsafe. */
if (isascii(ch) && !isalnum(ch))
*p++ = '\\';
}
*p++ = ch;
}
*p = '\0';
return bp;
alloc_err:
return NULL;
}
/*
* argv_uesc --
* Unescape an escaped ex and shell argument.
*
* PUBLIC: CHAR_T *argv_uesc(SCR *, EXCMD *, CHAR_T *, size_t);
*/
CHAR_T *
argv_uesc(SCR *sp, EXCMD *excp, CHAR_T *str, size_t len)
{
size_t blen;
CHAR_T *bp, *p;
GET_SPACE_GOTOW(sp, bp, blen, len + 1);
for (p = bp; len > 0; ++str, --len) {
if (IS_ESCAPE(sp, excp, *str)) {
if (--len < 1)
break;
++str;
} else if (*str == '\\') {
if (--len < 1)
break;
++str;
/* Check for double escaping. */
if (*str == '\\' && len > 1)
switch (str[1]) {
case '!': case '%': case '#':
++str;
--len;
}
}
*p++ = *str;
}
*p = '\0';
return bp;
alloc_err:
return NULL;
}
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