Up for discussion: User-provided commands for reading shell input

.circleci/config.yml

@@ -51,7 +51,7 @@ jobs:
           name: Test
           command: |
             mkdir -p ./test/results
-            ./es -s < ./test/test.es --junit ./test/tests/* > ./test/results/results.xml
+            ./es -ps < ./test/test.es --junit ./test/tests/* > ./test/results/results.xml
 
       - store_artifacts:
           path: ./test/results/

Makefile.in

@@ -56,15 +56,15 @@ VPATH = $(srcdir)
 HFILES	= config.h es.h gc.h input.h prim.h print.h sigmsgs.h \
 	  stdenv.h syntax.h term.h var.h
 CFILES	= access.c closure.c conv.c dict.c eval.c except.c fd.c gc.c glob.c \
-	  glom.c input.c heredoc.c history.c list.c main.c match.c open.c opt.c \
+	  glom.c input.c heredoc.c list.c main.c match.c open.c opt.c \
 	  prim-ctl.c prim-etc.c prim-io.c prim-sys.c prim.c print.c proc.c \
-	  sigmsgs.c signal.c split.c status.c str.c syntax.c term.c token.c \
-	  tree.c util.c var.c vec.c version.c y.tab.c dump.c
+	  readline.c sigmsgs.c signal.c split.c status.c str.c syntax.c term.c \
+	  token.c tree.c util.c var.c vec.c version.c y.tab.c dump.c
 OFILES	= access.o closure.o conv.o dict.o eval.o except.o fd.o gc.o glob.o \
-	  glom.o input.o heredoc.o history.o list.o main.o match.o open.o opt.o \
+	  glom.o input.o heredoc.o list.o main.o match.o open.o opt.o \
 	  prim-ctl.o prim-etc.o prim-io.o prim-sys.o prim.o print.o proc.o \
-	  sigmsgs.o signal.o split.o status.o str.o syntax.o term.o token.o \
-	  tree.o util.o var.o vec.o version.o y.tab.o
+	  readline.o sigmsgs.o signal.o split.o status.o str.o syntax.o term.o \
+	  token.o tree.o util.o var.o vec.o version.o y.tab.o
 OTHER	= Makefile parse.y mksignal
 GEN	= esdump y.tab.c y.tab.h y.output token.h sigmsgs.c initial.c
 
@@ -145,6 +145,7 @@ prim.o : prim.c es.h config.h stdenv.h prim.h
 prim-ctl.o : prim-ctl.c es.h config.h stdenv.h prim.h 
 prim-etc.o : prim-etc.c es.h config.h stdenv.h prim.h 
 prim-io.o : prim-io.c es.h config.h stdenv.h gc.h prim.h 
+readline.o : readline.c es.h config.h stdenv.h prim.h 
 prim-sys.o : prim-sys.c es.h config.h stdenv.h prim.h 
 print.o : print.c es.h config.h stdenv.h print.h 
 proc.o : proc.c es.h config.h stdenv.h prim.h 

es.h

@@ -136,7 +136,7 @@ extern List *sortlist(List *list);
 
 /* tree.c */
 
-extern Tree *mk(NodeKind VARARGS);
+extern Tree *gcmk(NodeKind VARARGS);
 
 
 /* closure.c */
@@ -188,6 +188,7 @@ extern List *extractmatches(List *subjects, List *patterns, StrList *quotes);
 
 extern void initvars(void);
 extern void initenv(char **envp, Boolean protected);
+extern void initgetenv(void);
 extern void hidevariables(void);
 extern void validatevar(const char *var);
 extern List *varlookup(const char *name, Binding *binding);
@@ -290,7 +291,7 @@ extern Boolean streq2(const char *s, const char *t1, const char *t2);
 /* input.c */
 
 extern char *prompt, *prompt2;
-extern Tree *parse(char *esprompt1, char *esprompt2);
+extern Tree *parse(List *);
 extern Tree *parsestring(const char *str);
 extern Boolean isinteractive(void);
 extern Boolean isfromfd(void);
@@ -307,8 +308,16 @@ extern List *runstring(const char *str, const char *name, int flags);
 #define	run_printcmds		32	/* -x */
 #define	run_lisptrees		64	/* -L and defined(LISPTREES) */
 
+
+/* readline.c */
+
 #if HAVE_READLINE
-extern Boolean resetterminal;
+extern void inithistory(void);
+
+extern void sethistory(char *file);
+extern void loghistory(char *cmd);
+extern void setmaxhistorylength(int length);
+extern void rlsetup(void);
 #endif
 
 
@@ -404,6 +413,11 @@ extern void gcenable(void);			/* enable collections */
 extern void gcdisable(void);			/* disable collections */
 extern Boolean gcisblocked(void);		/* is collection disabled? */
 
+extern void *palloc(size_t n, Tag *t);		/* allocate like gcalloc but in pspace */
+extern void *pseal(void *p);			/* collect pspace into gcspace with one root */
+extern char *pdup(const char *s);		/* copy a 0-terminated string into pspace */
+extern char *pndup(const char *s, size_t n);	/* copy a counted string into pspace */
+
 
 /*
  * garbage collector tags

gc.c

@@ -19,6 +19,7 @@ struct Space {
 #define	INSPACE(p, sp)	((sp)->bot <= (char *) (p) && (char *) (p) < (sp)->top)
 
 #define	MIN_minspace	10000
+#define	MIN_minpspace	5000
 
 #if GCPROTECT
 #define	NSPACES		10
@@ -38,13 +39,15 @@ int gcblocked = 0;
 Tag StringTag;
 
 /* own variables */
-static Space *new, *old;
+static Space *new, *old, *pspace;
 #if GCPROTECT
 static Space *spaces;
 #endif
 static Root *globalrootlist, *exceptionrootlist;
 static size_t minspace = MIN_minspace;	/* minimum number of bytes in a new space */
 
+static size_t minpspace = MIN_minpspace;	/* minimum number of bytes in a new pspace */
+
 
 /*
  * debugging
@@ -192,6 +195,18 @@ static Space *newspace(Space *next) {
 
 #endif	/* !GCPROTECT */
 
+/* newpspace -- create a new ``half'' space for use while parsing
+ * only exists to avoid gcprotect which I don't understand */
+static Space *newpspace(Space *next) {
+	size_t n = ALIGN(minpspace);
+	Space *space = ealloc(sizeof (Space) + n);
+	space->bot = (void *) &space[1];
+	space->top = (void *) (((char *) space->bot) + n);
+	space->current = space->bot;
+	space->next = next;
+	return space;
+}
+
 /* deprecate -- take a space and invalidate it */
 static void deprecate(Space *space) {
 #if GCPROTECT
@@ -222,7 +237,8 @@ static void deprecate(Space *space) {
 }
 
 /* isinspace -- does an object lie inside a given Space? */
-extern Boolean isinspace(Space *space, void *p) {
+extern Boolean isinspace(Space *space0, void *p) {
+	Space *space = space0;
 	for (; space != NULL; space = space->next)
 		if (INSPACE(p, space)) {
 		 	assert((char *) p < space->current);
@@ -273,12 +289,17 @@ extern void exceptionunroot(void) {
 #define	FOLLOWTO(p)	((Tag *) (((char *) p) + 1))
 #define	FOLLOW(tagp)	((void *) (((char *) tagp) - 1))
 
+static Boolean pmode = FALSE;
+
 /* forward -- forward an individual pointer from old space */
 extern void *forward(void *p) {
 	Tag *tag;
 	void *np;
 
-	if (!isinspace(old, p)) {
+	if (pmode && !isinspace(pspace, p)) {
+		VERBOSE(("GC %8ux : <<not in pspace>>\n", p));
+		return p;
+	} else if (!pmode && !isinspace(old, p)) {
 		VERBOSE(("GC %8ux : <<not in old space>>\n", p));
 		return p;
 	}
@@ -287,6 +308,7 @@ extern void *forward(void *p) {
 
 	tag = TAG(p);
 	assert(tag != NULL);
+
 	if (FORWARDED(tag)) {
 		np = FOLLOW(tag);
 		assert(TAG(np)->magic == TAGMAGIC);
@@ -297,6 +319,13 @@ extern void *forward(void *p) {
 		VERBOSE(("%s	-> %8ux (forwarded)\n", tag->typename, np));
 		TAG(p) = FOLLOWTO(np);
 	}
+
+	/* hack of the decade: recurse, sometimes */
+	if (pmode) {
+		tag = TAG(np);
+		(*tag->scan)(np);
+	}
+
 	return np;
 }
 
@@ -315,9 +344,7 @@ static void scanspace(void) {
 	for (scanned = NULL;;) {
 		Space *front = new;
 		for (sp = new; sp != scanned; sp = sp->next) {
-			char *scan;
-			assert(sp != NULL);
-			scan = sp->bot;
+			char *scan = sp->bot;
 			while (scan < sp->current) {
 				Tag *tag = *(Tag **) scan;
 				assert(tag->magic == TAGMAGIC);
@@ -439,6 +466,49 @@ extern void gc(void) {
 	} while (new->next != NULL);
 }
 
+/* pseal -- collect pspace to new, and translate p to its new location */
+extern void *pseal(void *p) {
+	size_t psize = 0;
+	Space *sp;
+
+	for (sp = pspace; sp != NULL; sp = sp->next)
+		psize += SPACEUSED(sp);
+
+	if (psize == 0)
+		return p;
+
+	/* TODO: this is an overestimate since it includes garbage */
+	gcreserve(psize);
+	pmode = TRUE;
+	VERBOSE(("Reserved %d for pspace copy\n", psize));
+
+	assert (gcblocked >= 0);
+	++gcblocked;
+
+#if GCVERBOSE
+	for (sp = pspace; sp != NULL; sp = sp->next)
+		VERBOSE(("GC pspace = %ux ... %ux\n", sp->bot, sp->current));
+#endif
+	if (p != NULL) {
+		VERBOSE(("GC new space = %ux ... %ux\n", new->bot, new->top));
+
+		p = forward(p);
+		(*(TAG(p))->scan)(p);
+	}
+
+	/* TODO: possible performance win: save+reuse the first pspace */
+	for (sp = pspace; sp != NULL;) {
+		Space *old = sp;
+		sp = sp->next;
+		efree(old);
+	}
+	pspace = newpspace(NULL);
+
+	--gcblocked;
+	pmode = FALSE;
+	return p;
+}
+
 /* initgc -- initialize the garbage collector */
 extern void initgc(void) {
 #if GCPROTECT
@@ -449,6 +519,7 @@ extern void initgc(void) {
 #else
 	new = newspace(NULL);
 #endif
+	pspace = newpspace(NULL);
 	old = NULL;
 }
 
@@ -481,6 +552,24 @@ extern void *gcalloc(size_t nbytes, Tag *tag) {
 	}
 }
 
+/* palloc -- allocate an object in pspace during parse */
+extern void *palloc(size_t nbytes, Tag *tag) {
+	size_t n = ALIGN(nbytes + sizeof (Tag *));
+	assert(tag == NULL || tag->magic == TAGMAGIC);
+	for (;;) {
+		Tag **p = (void *) pspace->current;
+		char *q = ((char *) p) + n;
+		if (q <= pspace->top) {
+			pspace->current = q;
+			*p++ = tag;
+			return p;
+		}
+		if (minpspace < nbytes)
+			minpspace = nbytes + sizeof (Tag *);
+		pspace = newpspace(pspace);
+	}
+}
+
 
 /*
  * strings
@@ -519,6 +608,22 @@ static size_t StringScan(void *p) {
 }
 
 
+extern char *pndup(const char *s, size_t n) {
+	char *ns;
+
+	ns = palloc((n + 1) * sizeof (char), &StringTag);
+	memcpy(ns, s, n);
+	ns[n] = '\0';
+	assert(strlen(ns) == n);
+
+	return ns;
+}
+
+extern char *pdup(const char *s) {
+	return pndup(s, strlen(s));
+}
+
+
 /*
  * allocation of large, contiguous buffers for large object creation
  *	see the use of this in str().  note that this region may not
@@ -547,12 +652,24 @@ extern char *sealbuffer(Buffer *buf) {
 	return s;
 }
 
+extern char *psealbuffer(Buffer *buf) {
+	char *s = pdup(buf->str);
+	efree(buf);
+	return s;
+}
+
 extern char *sealcountedbuffer(Buffer *buf) {
 	char *s = gcndup(buf->str, buf->current);
 	efree(buf);
 	return s;
 }
 
+extern char *psealcountedbuffer(Buffer *buf) {
+	char *s = pndup(buf->str, buf->current);
+	efree(buf);
+	return s;
+}
+
 extern Buffer *bufncat(Buffer *buf, const char *s, size_t len) {
 	while (buf->current + len >= buf->len)
 		buf = expandbuffer(buf, buf->current + len - buf->len);

gc.h

@@ -50,6 +50,8 @@ extern Buffer *bufcat(Buffer *buf, const char *s);
 extern Buffer *bufputc(Buffer *buf, char c);
 extern char *sealbuffer(Buffer *buf);
 extern char *sealcountedbuffer(Buffer *buf);
+extern char *psealbuffer(Buffer *buf);
+extern char *psealcountedbuffer(Buffer *buf);
 extern void freebuffer(Buffer *buf);
 
 extern void *forward(void *p);

heredoc.c

@@ -22,7 +22,7 @@ extern Tree *getherevar(void) {
 	while ((c = GETC()) != EOF && !dnw[c])
 		buf = bufputc(buf, c);
 	len = buf->len;
-	s = sealcountedbuffer(buf);
+	s = psealcountedbuffer(buf);
 	if (len == 0) {
 		yyerror("null variable name in here document");
 		return NULL;
@@ -47,14 +47,14 @@ extern Tree *snarfheredoc(const char *eof, Boolean quoted) {
 
 	for (tree = NULL, tailp = &tree, buf = openbuffer(0);;) {
 		int c;
-		print_prompt2();
+		increment_line();
 		for (s = (unsigned char *) eof; (c = GETC()) == *s; s++)
 			;
 		if (*s == '\0' && (c == '\n' || c == EOF)) {
 			if (buf->current == 0 && tree != NULL)
 				freebuffer(buf);
 			else
-				*tailp = treecons(mk(nQword, sealcountedbuffer(buf)), NULL);
+				*tailp = treecons(mk(nQword, psealcountedbuffer(buf)), NULL);
 			break;
 		}
 		if (s != (unsigned char *) eof)
@@ -72,7 +72,7 @@ extern Tree *snarfheredoc(const char *eof, Boolean quoted) {
 				if (buf->current == 0)
 					freebuffer(buf);
 				else {
-					*tailp = treecons(mk(nQword, sealcountedbuffer(buf)), NULL);
+					*tailp = treecons(mk(nQword, psealcountedbuffer(buf)), NULL);
 					tailp = &(*tailp)->CDR;
 				}
 				var = getherevar();
@@ -133,7 +133,7 @@ extern Boolean queueheredoc(Tree *t) {
 		return FALSE;
 	}
 
-	here = gcalloc(sizeof (Here), NULL);
+	here = palloc(sizeof (Here), NULL);
 	here->next = hereq;
 	here->marker = eof;
 	hereq = here;