Understand gcc directive #include_next. Solves Jira#PCC-106 by Altamiranus.

3 files changed, 59 insertions, 19 deletions

diff --git a/cpp.c b/cpp.c
index 92ac324..aac6129 100644
--- a/cpp.c
+++ b/cpp.c
@@ -171,6 +171,7 @@ static void expdef(usch *proto, struct recur *, int gotwarn);
 void define(void);
 static int canexpand(struct recur *, struct symtab *np);
 void include(void);
+void include_next(void);
 void line(void);
 void flbuf(void);
 void usage(void);
@@ -185,6 +186,7 @@ main(int argc, char **argv)
 	struct incs *w, *w2;
 	struct symtab *nl;
 	register int ch;
+	usch *fn1, *fn2;
 
 #ifdef TIMING
 	struct timeval t1, t2;
@@ -316,7 +318,13 @@ main(int argc, char **argv)
 		ofd = 1; /* stdout */
 	istty = isatty(ofd);
 
-	if (pushfile((usch *)(argc && strcmp(argv[0], "-") ? argv[0] : NULL)))
+	if (argc && strcmp(argv[0], "-")) {
+		fn1 = fn2 = (usch *)argv[0];
+	} else {
+		fn1 = NULL;
+		fn2 = (usch *)"";
+	}
+	if (pushfile(fn1, fn2, 0, NULL))
 		error("cannot open %s", argv[0]);
 
 	flbuf();
@@ -485,6 +493,31 @@ bad:	error("bad line directive");
 }
 
 /*
+ * Search for and include next file.
+ * Return 1 on success.
+ */
+static int
+fsrch(usch *fn, int idx, struct incs *w)
+{
+	int i;
+
+	for (i = idx; i < 2; i++) {
+		if (i > idx)
+			w = incdir[i];
+		for (; w; w = w->next) {
+			usch *nm = stringbuf;
+
+			savstr(w->dir); savch('/');
+			savstr(fn); savch(0);
+			if (pushfile(nm, fn, i, w->next) == 0)
+				return 1;
+			stringbuf = nm;
+		}
+	}
+	return 0;
+}
+
+/*
  * Include a file. Include order:
  * - For <...> files, first search -I directories, then system directories.
  * - For "..." files, first search "current" dir, then as <...> files.
@@ -493,10 +526,9 @@ void
 include()
 {
 	struct symtab *nl;
-	struct incs *w;
 	usch *osp;
 	usch *fn, *safefn;
-	int i, c, it;
+	int c, it;
 
 	if (flslvl)
 		return;
@@ -549,23 +581,14 @@ include()
 		c = yylex();
 		if (c != '\n')
 			goto bad;
-		if (pushfile(nm) == 0)
+		if (pushfile(nm, safefn, 0, NULL) == 0)
 			goto okret;
 		/* XXX may loose stringbuf space */
 	}
 
-	/* create search path and try to open file */
-	for (i = 0; i < 2; i++) {
-		for (w = incdir[i]; w; w = w->next) {
-			usch *nm = stringbuf;
+	if (fsrch(safefn, 0, incdir[0]))
+		goto okret;
 
-			savstr(w->dir); savch('/');
-			savstr(safefn); savch(0);
-			if (pushfile(nm) == 0)
-				goto okret;
-			stringbuf = nm;
-		}
-	}
 	error("cannot find '%s'", safefn);
 	/* error() do not return */
 
@@ -575,6 +598,13 @@ okret:
 	prtline();
 }
 
+void
+include_next()
+{
+	if (fsrch(ifiles->fn, ifiles->idx, ifiles->incs) == 0)
+		error("cannot find '%s'", ifiles->fn);
+}
+
 static int
 definp(void)
 {
diff --git a/cpp.h b/cpp.h
index fd62803..2b3ad22 100644
--- a/cpp.h
+++ b/cpp.h
@@ -78,6 +78,9 @@ struct includ {
 	usch *maxread;
 	usch *ostr;
 	usch *buffer;
+	int idx;
+	void *incs;
+	usch *fn;
 	usch bbuf[NAMEMAX+CPPBUF+1];
 } *ifiles;
 
@@ -118,7 +121,7 @@ struct symtab *lookup(usch *namep, int enterf);
 usch *gotident(struct symtab *nl);
 int slow;	/* scan slowly for new tokens */
 
-int pushfile(usch *fname);
+int pushfile(usch *fname, usch *fn, int idx, void *incs);
 void popfile(void);
 void prtline(void);
 int yylex(void);
diff --git a/token.c b/token.c
index 3201cc0..f377be9 100644
--- a/token.c
+++ b/token.c
@@ -71,6 +71,7 @@ static void badop(const char *);
 static int chktg(void);
 static void ppdir(void);
 void  include(void);
+void  include_next(void);
 void  define(void);
 static int inpch(void);
 
@@ -672,7 +673,7 @@ prinit(struct initar *it, struct includ *ic)
  * Return 0 on success, -1 if file to be included is not found.
  */
 int
-pushfile(usch *file)
+pushfile(usch *file, usch *fn, int idx, void *incs)
 {
 	extern struct initar *initar;
 	struct includ ibuf;
@@ -697,6 +698,9 @@ pushfile(usch *file)
 	ifiles = ic;
 	ic->lineno = 1;
 	ic->maxread = ic->curptr;
+	ic->idx = idx;
+	ic->incs = incs;
+	ic->fn = fn;
 	prtline();
 	if (initar) {
 		*ic->maxread = 0;
@@ -1117,6 +1121,9 @@ static struct {
 	{ "line", line },
 	{ "pragma", pragmastmt },
 	{ "elif", elifstmt },
+#ifdef GCC_COMPAT
+	{ "include_next", include_next },
+#endif
 };
 
 /*
@@ -1125,7 +1132,7 @@ static struct {
 void
 ppdir(void)
 {
-	char bp[10];
+	char bp[20];
 	int ch, i;
 
 	while ((ch = inch()) == ' ' || ch == '\t')
@@ -1138,7 +1145,7 @@ ppdir(void)
 		if (i == sizeof(bp)-1)
 			goto out; /* too long */
 		ch = inch();
-	} while (ch >= 'a' && ch <= 'z');
+	} while ((ch >= 'a' && ch <= 'z') || (ch == '_'));
 	unch(ch);
 	bp[i++] = 0;