From 6b8f3f9906ee44be46e022480b6e01755feeaa99 Mon Sep 17 00:00:00 2001

From: Peter Stephenson <pws@zsh.org>

Date: Tue, 6 Jan 2015 17:05:17 +0000

Subject: [PATCH 1/4] Fix command substitutions to parse contents as they are

 read in.

Do this by refactoring misnamed lexsave()/lexrestore() to allow

continuity of history and input.

Add test.

Upstream-commit: c0d01a6fe0c67911650730cf13a2b9a0db16e59b

Signed-off-by: Kamil Dudka <kdudka@redhat.com>

---

 Src/init.c            |   3 +-

 Src/input.c           |  13 +-

 Src/lex.c             | 498 ++++++++++++++++++++++++++++++++------------------

 Src/parse.c           |  29 ++-

 Src/zsh.h             |   9 +

 Test/D08cmdsubst.ztst |  42 +++++

 6 files changed, 401 insertions(+), 193 deletions(-)

diff --git a/Src/init.c b/Src/init.c

index 0742a9f..78f171d 100644

--- a/Src/init.c

+++ b/Src/init.c

@@ -129,7 +129,8 @@ loop(int toplevel, int justonce)

 	use_exit_printed = 0;

 	intr();			/* interrupts on            */

 	lexinit();              /* initialize lexical state */

-	if (!(prog = parse_event())) {	/* if we couldn't parse a list */

+	if (!(prog = parse_event(ENDINPUT))) {

+	    /* if we couldn't parse a list */

 	    hend(NULL);

 	    if ((tok == ENDINPUT && !errflag) ||

 		(tok == LEXERR && (!isset(SHINSTDIN) || !toplevel)) ||

diff --git a/Src/input.c b/Src/input.c

index 5cff22d..1579762 100644

--- a/Src/input.c

+++ b/Src/input.c

@@ -175,12 +175,12 @@ shingetline(void)

 /* Get the next character from the input.

  * Will call inputline() to get a new line where necessary.

  */

-  

+

 /**/

 int

 ingetc(void)

 {

-    int lastc;

+    int lastc = ' ';

     if (lexstop)

 	return ' ';

@@ -192,7 +192,7 @@ ingetc(void)

 		continue;

 	    if (((inbufflags & INP_LINENO) || !strin) && lastc == '\n')

 		lineno++;

-	    return lastc;

+	    break;

 	}

 	/*

@@ -204,7 +204,7 @@ ingetc(void)

 	 */

 	if (!inbufct && (strin || errflag)) {

 	    lexstop = 1;

-	    return ' ';

+	    break;

 	}

 	/* If the next element down the input stack is a continuation of

 	 * this, use it.

@@ -215,8 +215,10 @@ ingetc(void)

 	}

 	/* As a last resort, get some more input */

 	if (inputline())

-	    return ' ';

+	    break;

     }

+    zshlex_raw_add(lastc);

+    return lastc;

 }

 /* Read a line from the current command stream and store it as input */

@@ -421,6 +423,7 @@ inungetc(int c)

 	    inbufleft = 0;

 	    inbuf = inbufptr = "";

 	}

+	zshlex_raw_back();

     }

 }

diff --git a/Src/lex.c b/Src/lex.c

index 82bf848..bcceda6 100644

--- a/Src/lex.c

+++ b/Src/lex.c

@@ -146,6 +146,16 @@ mod_export int parend;

 /**/

 mod_export int nocomments;

+/* add raw input characters while parsing command substitution */

+

+/**/

+static int lex_add_raw;

+

+/* variables associated with the above */

+

+static char *tokstr_raw, *bptr_raw;

+static int len_raw, bsiz_raw;

+

 /* text of punctuation tokens */

 /**/

@@ -214,6 +224,11 @@ struct lexstack {

     char *bptr;

     int bsiz;

     int len;

+    int lex_add_raw;

+    char *tokstr_raw;

+    char *bptr_raw;

+    int bsiz_raw;

+    int len_raw;

     short *chwords;

     int chwordlen;

     int chwordpos;

@@ -239,89 +254,121 @@ struct lexstack {

 static struct lexstack *lstack = NULL;

-/* save the lexical state */

+/* save the context or parts thereof */

 /* is this a hack or what? */

 /**/

 mod_export void

-lexsave(void)

+lexsave_partial(int parts)

 {

     struct lexstack *ls;

     ls = (struct lexstack *)malloc(sizeof(struct lexstack));

-    ls->incmdpos = incmdpos;

-    ls->incond = incond;

-    ls->incasepat = incasepat;

-    ls->dbparens = dbparens;

-    ls->isfirstln = isfirstln;

-    ls->isfirstch = isfirstch;

-    ls->histactive = histactive;

-    ls->histdone = histdone;

-    ls->lexflags = lexflags;

-    ls->stophist = stophist;

-    stophist = 0;

-    if (!lstack) {

-	/* top level, make this version visible to ZLE */

-	zle_chline = chline;

-	/* ensure line stored is NULL-terminated */

-	if (hptr)

-	    *hptr = '\0';

+    if (parts & ZCONTEXT_LEX) {

+	ls->incmdpos = incmdpos;

+	ls->incond = incond;

+	ls->incasepat = incasepat;

+	ls->dbparens = dbparens;

+	ls->isfirstln = isfirstln;

+	ls->isfirstch = isfirstch;

+	ls->lexflags = lexflags;

+

+	ls->tok = tok;

+	ls->isnewlin = isnewlin;

+	ls->tokstr = tokstr;

+	ls->zshlextext = zshlextext;

+	ls->bptr = bptr;

+	ls->bsiz = bsiz;

+	ls->len = len;

+	ls->lex_add_raw = lex_add_raw;

+	ls->tokstr_raw = tokstr_raw;

+	ls->bptr_raw = bptr_raw;

+	ls->bsiz_raw = bsiz_raw;

+	ls->len_raw = len_raw;

+	ls->lexstop = lexstop;

+	ls->toklineno = toklineno;

+

+	tokstr = zshlextext = bptr = NULL;

+	bsiz = 256;

+	tokstr_raw = bptr_raw = NULL;

+	bsiz_raw = len_raw = lex_add_raw = 0;

+

+	inredir = 0;

+    }

+    if (parts & ZCONTEXT_HIST) {

+	if (!lstack) {

+	    /* top level, make this version visible to ZLE */

+	    zle_chline = chline;

+	    /* ensure line stored is NULL-terminated */

+	    if (hptr)

+		*hptr = '\0';

+	}

+	ls->histactive = histactive;

+	ls->histdone = histdone;

+	ls->stophist = stophist;

+	ls->hline = chline;

+	ls->hptr = hptr;

+	ls->chwords = chwords;

+	ls->chwordlen = chwordlen;

+	ls->chwordpos = chwordpos;

+	ls->hwgetword = hwgetword;

+	ls->hgetc = hgetc;

+	ls->hungetc = hungetc;

+	ls->hwaddc = hwaddc;

+	ls->hwbegin = hwbegin;

+	ls->hwend = hwend;

+	ls->addtoline = addtoline;

+	ls->hlinesz = hlinesz;

+	/*

+	 * We save and restore the command stack with history

+	 * as it's visible to the user interactively, so if

+	 * we're preserving history state we'll continue to

+	 * show the current set of commands from input.

+	 */

+	ls->cstack = cmdstack;

+	ls->csp = cmdsp;

+

+	stophist = 0;

+	chline = NULL;

+	hptr = NULL;

+	histactive = 0;

+	cmdstack = (unsigned char *)zalloc(CMDSTACKSZ);

+	cmdsp = 0;

+    }

+    if (parts & ZCONTEXT_PARSE) {

+	ls->hdocs = hdocs;

+	ls->eclen = eclen;

+	ls->ecused = ecused;

+	ls->ecnpats = ecnpats;

+	ls->ecbuf = ecbuf;

+	ls->ecstrs = ecstrs;

+	ls->ecsoffs = ecsoffs;

+	ls->ecssub = ecssub;

+	ls->ecnfunc = ecnfunc;

+	ecbuf = NULL;

+	hdocs = NULL;

     }

-    ls->hline = chline;

-    chline = NULL;

-    ls->hptr = hptr;

-    hptr = NULL;

-    ls->hlinesz = hlinesz;

-    ls->cstack = cmdstack;

-    ls->csp = cmdsp;

-    cmdstack = (unsigned char *)zalloc(CMDSTACKSZ);

-    ls->tok = tok;

-    ls->isnewlin = isnewlin;

-    ls->tokstr = tokstr;

-    ls->zshlextext = zshlextext;

-    ls->bptr = bptr;

-    tokstr = zshlextext = bptr = NULL;

-    ls->bsiz = bsiz;

-    bsiz = 256;

-    ls->len = len;

-    ls->chwords = chwords;

-    ls->chwordlen = chwordlen;

-    ls->chwordpos = chwordpos;

-    ls->hwgetword = hwgetword;

-    ls->lexstop = lexstop;

-    ls->hdocs = hdocs;

-    ls->hgetc = hgetc;

-    ls->hungetc = hungetc;

-    ls->hwaddc = hwaddc;

-    ls->hwbegin = hwbegin;

-    ls->hwend = hwend;

-    ls->addtoline = addtoline;

-    ls->eclen = eclen;

-    ls->ecused = ecused;

-    ls->ecnpats = ecnpats;

-    ls->ecbuf = ecbuf;

-    ls->ecstrs = ecstrs;

-    ls->ecsoffs = ecsoffs;

-    ls->ecssub = ecssub;

-    ls->ecnfunc = ecnfunc;

-    ls->toklineno = toklineno;

-    cmdsp = 0;

-    inredir = 0;

-    hdocs = NULL;

-    histactive = 0;

-    ecbuf = NULL;

     ls->next = lstack;

     lstack = ls;

 }

-/* restore lexical state */

+/* save context in full */

 /**/

 mod_export void

-lexrestore(void)

+lexsave(void)

+{

+    lexsave_partial(ZCONTEXT_HIST|ZCONTEXT_LEX|ZCONTEXT_PARSE);

+}

+

+/* restore context or part therefore */

+

+/**/

+mod_export void

+lexrestore_partial(int parts)

 {

     struct lexstack *ln = lstack;

@@ -330,65 +377,89 @@ lexrestore(void)

     queue_signals();

     lstack = lstack->next;

-    if (!lstack) {

-	/* Back to top level: don't need special ZLE value */

-	DPUTS(ln->hline != zle_chline, "BUG: Ouch, wrong chline for ZLE");

-	zle_chline = NULL;

+    if (parts & ZCONTEXT_LEX) {

+	incmdpos = ln->incmdpos;

+	incond = ln->incond;

+	incasepat = ln->incasepat;

+	dbparens = ln->dbparens;

+	isfirstln = ln->isfirstln;

+	isfirstch = ln->isfirstch;

+	lexflags = ln->lexflags;

+	tok = ln->tok;

+	isnewlin = ln->isnewlin;

+	tokstr = ln->tokstr;

+	zshlextext = ln->zshlextext;

+	bptr = ln->bptr;

+	bsiz = ln->bsiz;

+	len = ln->len;

+	lex_add_raw = ln->lex_add_raw;

+	tokstr_raw = ln->tokstr_raw;

+	bptr_raw = ln->bptr_raw;

+	bsiz_raw = ln->bsiz_raw;

+	len_raw = ln->len_raw;

+	lexstop = ln->lexstop;

+	toklineno = ln->toklineno;

+    }

+

+    if (parts & ZCONTEXT_HIST) {

+	if (!lstack) {

+	    /* Back to top level: don't need special ZLE value */

+	    DPUTS(ln->hline != zle_chline, "BUG: Ouch, wrong chline for ZLE");

+	    zle_chline = NULL;

+	}

+	histactive = ln->histactive;

+	histdone = ln->histdone;

+	stophist = ln->stophist;

+	chline = ln->hline;

+	hptr = ln->hptr;

+	chwords = ln->chwords;

+	chwordlen = ln->chwordlen;

+	chwordpos = ln->chwordpos;

+	hwgetword = ln->hwgetword;

+	hgetc = ln->hgetc;

+	hungetc = ln->hungetc;

+	hwaddc = ln->hwaddc;

+	hwbegin = ln->hwbegin;

+	hwend = ln->hwend;

+	addtoline = ln->addtoline;

+	hlinesz = ln->hlinesz;

+	if (cmdstack)

+	    zfree(cmdstack, CMDSTACKSZ);

+	cmdstack = ln->cstack;

+	cmdsp = ln->csp;

+    }

+

+    if (parts & ZCONTEXT_PARSE) {

+	if (ecbuf)

+	    zfree(ecbuf, eclen);

+

+	hdocs = ln->hdocs;

+	eclen = ln->eclen;

+	ecused = ln->ecused;

+	ecnpats = ln->ecnpats;

+	ecbuf = ln->ecbuf;

+	ecstrs = ln->ecstrs;

+	ecsoffs = ln->ecsoffs;

+	ecssub = ln->ecssub;

+	ecnfunc = ln->ecnfunc;

+

+	errflag = 0;

     }

-    incmdpos = ln->incmdpos;

-    incond = ln->incond;

-    incasepat = ln->incasepat;

-    dbparens = ln->dbparens;

-    isfirstln = ln->isfirstln;

-    isfirstch = ln->isfirstch;

-    histactive = ln->histactive;

-    histdone = ln->histdone;

-    lexflags = ln->lexflags;

-    stophist = ln->stophist;

-    chline = ln->hline;

-    hptr = ln->hptr;

-    if (cmdstack)

-	zfree(cmdstack, CMDSTACKSZ);

-    cmdstack = ln->cstack;

-    cmdsp = ln->csp;

-    tok = ln->tok;

-    isnewlin = ln->isnewlin;

-    tokstr = ln->tokstr;

-    zshlextext = ln->zshlextext;

-    bptr = ln->bptr;

-    bsiz = ln->bsiz;

-    len = ln->len;

-    chwords = ln->chwords;

-    chwordlen = ln->chwordlen;

-    chwordpos = ln->chwordpos;

-    hwgetword = ln->hwgetword;

-    lexstop = ln->lexstop;

-    hdocs = ln->hdocs;

-    hgetc = ln->hgetc;

-    hungetc = ln->hungetc;

-    hwaddc = ln->hwaddc;

-    hwbegin = ln->hwbegin;

-    hwend = ln->hwend;

-    addtoline = ln->addtoline;

-    if (ecbuf)

-	zfree(ecbuf, eclen);

-    eclen = ln->eclen;

-    ecused = ln->ecused;

-    ecnpats = ln->ecnpats;

-    ecbuf = ln->ecbuf;

-    ecstrs = ln->ecstrs;

-    ecsoffs = ln->ecsoffs;

-    ecssub = ln->ecssub;

-    ecnfunc = ln->ecnfunc;

-    hlinesz = ln->hlinesz;

-    toklineno = ln->toklineno;

-    errflag = 0;

     free(ln);

     unqueue_signals();

 }

+/* complete restore context */

+

+/**/

+mod_export void

+lexrestore(void)

+{

+    lexrestore_partial(ZCONTEXT_HIST|ZCONTEXT_LEX|ZCONTEXT_PARSE);

+}

+

 /**/

 void

 zshlex(void)

@@ -1889,80 +1960,151 @@ exalias(void)

     return 0;

 }

-/* skip (...) */

+/**/

+void

+zshlex_raw_add(int c)

+{

+    if (!lex_add_raw)

+	return;

+

+    *bptr_raw++ = c;

+    if (bsiz_raw == ++len_raw) {

+	int newbsiz = bsiz_raw * 2;

+

+	tokstr_raw = (char *)hrealloc(tokstr_raw, bsiz_raw, newbsiz);

+	bptr_raw = tokstr_raw + len_raw;

+	memset(bptr_raw, 0, newbsiz - bsiz_raw);

+	bsiz_raw = newbsiz;

+    }

+}

+

+/**/

+void

+zshlex_raw_back(void)

+{

+    if (!lex_add_raw)

+	return;

+    bptr_raw--;

+    len_raw--;

+}

+

+/*

+ * Skip (...) for command-style substitutions: $(...), <(...), >(...)

+ *

+ * In order to ensure we don't stop at closing parentheses with

+ * some other syntactic significance, we'll parse the input until

+ * we find an unmatched closing parenthesis.  However, we'll throw

+ * away the result of the parsing and just keep the string we've built

+ * up on the way.

+ */

 /**/

 static int

 skipcomm(void)

 {

-    int pct = 1, c, start = 1;

+    char *new_tokstr, *new_bptr = bptr_raw;

+    int new_len, new_bsiz, new_lexstop, new_lex_add_raw;

     cmdpush(CS_CMDSUBST);

     SETPARBEGIN

-    c = Inpar;

-    do {

-	int iswhite;

-	add(c);

-	c = hgetc();

-	if (itok(c) || lexstop)

-	    break;

-	iswhite = inblank(c);

-	switch (c) {

-	case '(':

-	    pct++;

-	    break;

-	case ')':

-	    pct--;

-	    break;

-	case '\\':

-	    add(c);

-	    c = hgetc();

-	    break;

-	case '\'': {

-	    int strquote = bptr[-1] == '$';

-	    add(c);

-	    STOPHIST

-	    while ((c = hgetc()) != '\'' && !lexstop) {

-		if (c == '\\' && strquote) {

-		    add(c);

-		    c = hgetc();

-		}

-		add(c);

-	    }

-	    ALLOWHIST

-	    break;

-	}

-	case '\"':

-	    add(c);

-	    while ((c = hgetc()) != '\"' && !lexstop)

-		if (c == '\\') {

-		    add(c);

-		    add(hgetc());

-		} else

-		    add(c);

-	    break;

-	case '`':

-	    add(c);

-	    while ((c = hgetc()) != '`' && !lexstop)

-		if (c == '\\')

-		    add(c), add(hgetc());

-		else

-		    add(c);

-	    break;

-	case '#':

-	    if (start) {

-		add(c);

-		while ((c = hgetc()) != '\n' && !lexstop)

-		    add(c);

-		iswhite = 1;

-	    }

-	    break;

+    add(Inpar);

+

+    new_lex_add_raw = lex_add_raw + 1;

+    if (!lex_add_raw) {

+	/*

+	 * We'll combine the string so far with the input

+	 * read in for the command substitution.  To do this

+	 * we'll just propagate the current tokstr etc. as the

+	 * variables used for adding raw input, and

+	 * ensure we swap those for the real tokstr etc. at the end.

+	 *

+	 * However, we need to save and restore the rest of the

+	 * lexical and parse state as we're effectively parsing

+	 * an internal string.  Because we're still parsing it from

+	 * the original input source (we have to --- we don't know

+	 * when to stop inputting it otherwise and can't rely on

+	 * the input being recoverable until we've read it) we need

+	 * to keep the same history context.

+	 */

+	new_tokstr = tokstr;

+	new_bptr = bptr;

+	new_len = len;

+	new_bsiz = bsiz;

+

+	lexsave_partial(ZCONTEXT_LEX|ZCONTEXT_PARSE);

+    } else {

+	/*

+	 * Set up for nested command subsitution, however

+	 * we don't actually need the string until we get

+	 * back to the top level and recover the lot.

+	 * The $() body just appears empty.

+	 *

+	 * We do need to propagate the raw variables which would

+	 * otherwise by cleared, though.

+	 */

+	new_tokstr = tokstr_raw;

+	new_bptr = bptr_raw;

+	new_len = len_raw;

+	new_bsiz = bsiz_raw;

+

+	lexsave_partial(ZCONTEXT_LEX|ZCONTEXT_PARSE);

+    }

+    tokstr_raw = new_tokstr;

+    bsiz_raw = new_bsiz;

+    len_raw = new_len;

+    bptr_raw = new_bptr;

+    lex_add_raw = new_lex_add_raw;

+

+    if (!parse_event(OUTPAR) || tok != OUTPAR)

+	lexstop = 1;

+     /* Outpar lexical token gets added in caller if present */

+

+    /*

+     * We're going to keep the full raw input string

+     * as the current token string after popping the stack.

+     */

+    new_tokstr = tokstr_raw;

+    new_bptr = bptr_raw;

+    new_len = len_raw;

+    new_bsiz = bsiz_raw;

+    /*

+     * We're also going to propagate the lexical state:

+     * if we couldn't parse the command substitution we

+     * can't continue.

+     */

+    new_lexstop = lexstop;

+

+    lexrestore_partial(ZCONTEXT_LEX|ZCONTEXT_PARSE);

+

+    if (lex_add_raw) {

+	/*

+	 * Keep going, so retain the raw variables.

+	 */

+	tokstr_raw = new_tokstr;

+	bptr_raw = new_bptr;

+	len_raw = new_len;

+	bsiz_raw = new_bsiz;

+    } else {

+	if (!new_lexstop) {

+	    /* Ignore the ')' added on input */

+	    new_len--;

+	    *--new_bptr = '\0';

 	}

-	start = iswhite;

+

+	/*

+	 * Convince the rest of lex.c we were examining a string

+	 * all along.

+	 */

+	tokstr = new_tokstr;

+	bptr = new_bptr;

+	len = new_len;

+	bsiz = new_bsiz;

+	lexstop = new_lexstop;

     }

-    while (pct);

+

     if (!lexstop)

 	SETPAREND

     cmdpop();

+

     return lexstop;

 }

diff --git a/Src/parse.c b/Src/parse.c

index 753080d..b0a7624 100644

--- a/Src/parse.c

+++ b/Src/parse.c

@@ -360,7 +360,8 @@ ecstrcode(char *s)

 /* Initialise wordcode buffer. */

-static void

+/**/

+void

 init_parse(void)

 {

     if (ecbuf) zfree(ecbuf, eclen);

@@ -439,11 +440,15 @@ clear_hdocs()

  * event	: ENDINPUT

  *			| SEPER

  *			| sublist [ SEPER | AMPER | AMPERBANG ]

+ *

+ * cmdsubst indicates our event is part of a command-style

+ * substitution terminated by the token indicationg, usual closing

+ * parenthesis.  In other cases endtok is ENDINPUT.

  */

 /**/

 Eprog

-parse_event(void)

+parse_event(int endtok)

 {

     tok = ENDINPUT;

     incmdpos = 1;

@@ -451,36 +456,42 @@ parse_event(void)

     zshlex();

     init_parse();

-    if (!par_event()) {

+    if (!par_event(endtok)) {

         clear_hdocs();

         return NULL;

     }

+    if (endtok != ENDINPUT) {

+	/* don't need to build an eprog for this */

+	return &dummy_eprog;

+    }

     return bld_eprog();

 }

 /**/

-static int

-par_event(void)

+int