Info backend now takes care to avoid magic characters in node names

and index terms (the Info format doesn't like them). In the course
of this I've had to introduce some infrastructure for carrying a
filepos forward from the definition of every RHS index term so that
a particular backend can provide a usefully localised report of
which index term had a problem.

[originally from svn r4051]

1 files changed, 13 insertions, 2 deletions

diff --git a/index.c b/index.c
index c312f07..9850750 100644
--- a/index.c
+++ b/index.c
@@ -21,6 +21,7 @@ static indextag *make_indextag(void) {
     ret->name = NULL;
     ret->implicit_text = NULL;
     ret->explicit_texts = NULL;
+    ret->explicit_fpos = NULL;
     ret->nexplicit = ret->explicit_size = ret->nrefs = 0;
     ret->refs = NULL;
     return ret;
@@ -57,7 +58,8 @@ indextag *index_findtag(indexdata *idx, wchar_t *name) {
  * Guarantee on calling sequence: all implicit merges are given
  * before the explicit ones.
  */
-void index_merge(indexdata *idx, int is_explicit, wchar_t *tags, word *text) {
+void index_merge(indexdata *idx, int is_explicit, wchar_t *tags, word *text,
+		 filepos *fpos) {
     indextag *t, *existing;
 
     /*
@@ -105,6 +107,7 @@ void index_merge(indexdata *idx, int is_explicit, wchar_t *tags, word *text) {
 	     * Otherwise, this is a new tag with an implicit \IM.
 	     */
 	    t->implicit_text = text;
+	    t->implicit_fpos = *fpos;
 	} else {
 	    sfree(t);
 	    t = existing;
@@ -130,8 +133,12 @@ void index_merge(indexdata *idx, int is_explicit, wchar_t *tags, word *text) {
 		    t->explicit_size = t->nexplicit + 8;
 		    t->explicit_texts = resize(t->explicit_texts,
 					       t->explicit_size);
+		    t->explicit_fpos = resize(t->explicit_fpos,
+					      t->explicit_size);
 		}
-		t->explicit_texts[t->nexplicit++] = text;
+		t->explicit_texts[t->nexplicit] = text;
+		t->explicit_fpos[t->nexplicit] = *fpos;
+		t->nexplicit++;
 	    }
 	}
     }
@@ -147,6 +154,7 @@ void index_merge(indexdata *idx, int is_explicit, wchar_t *tags, word *text) {
 void build_index(indexdata *i) {
     indextag *t;
     word **ta;
+    filepos *fa;
     int ti;
     int j;
 
@@ -154,15 +162,18 @@ void build_index(indexdata *i) {
 	if (t->implicit_text) {
 	    t->nrefs = 1;
 	    ta = &t->implicit_text;
+	    fa = &t->implicit_fpos;
 	} else {
 	    t->nrefs = t->nexplicit;
 	    ta = t->explicit_texts;
+	    fa = t->explicit_fpos;
 	}
 	if (t->nrefs) {
 	    t->refs = mknewa(indexentry *, t->nrefs);
 	    for (j = 0; j < t->nrefs; j++) {
 		indexentry *ent = mknew(indexentry);
 		ent->text = *ta++;
+		ent->fpos = *fa++;
 		t->refs[j] = add234(i->entries, ent);
 		if (t->refs[j] != ent)     /* duplicate */
 		    sfree(ent);