X-Git-Url: http://git.indexdata.com/?a=blobdiff_plain;f=src%2Fnfa.c;h=90bb040c72e9aba83293e8c2a4bf3b56b030fa94;hb=821e247a6d064e29703c74b21f755baaf4cc1e6e;hp=0eee5e8ad4a334ec1c87b985a5ff5e5d639d2a10;hpb=2af6f28e5d261fa873d96611a10c56fc76681685;p=yaz-moved-to-github.git

diff --git a/src/nfa.c b/src/nfa.c
index 0eee5e8..90bb040 100644
--- a/src/nfa.c
+++ b/src/nfa.c
@@ -1,7 +1,7 @@
 /*  Copyright (C) 2006, Index Data ApS
  *  See the file LICENSE for details.
  * 
- *  $Id: nfa.c,v 1.5 2006-05-04 18:58:54 adam Exp $ 
+ *  $Id: nfa.c,v 1.8 2006-05-05 14:04:03 heikki Exp $ 
  */
 
 /**
@@ -75,6 +75,21 @@ struct yaz_nfa_transition {
 #define LOOP_LIMIT 100
 
 
+typedef enum {
+    conv_none,
+    conv_string,
+    conv_backref,
+    conv_range
+} yaz_nfa_converter_type;
+
+struct yaz_nfa_converter {
+    yaz_nfa_converter *next;
+    yaz_nfa_converter_type type;
+    yaz_nfa_char *string;
+    size_t strlen;
+    int backref_no;
+    int char_diff;
+};
 
 
 /* * * * * * *
@@ -177,6 +192,8 @@ void yaz_nfa_add_transition(yaz_nfa *n,
         yaz_nfa_char range_start, 
         yaz_nfa_char range_end) {
     yaz_nfa_transition *t = nmem_malloc(n->nmem, sizeof(yaz_nfa_transition));
+    if (!from_state)
+        from_state = n->firststate;
     t->range_start = range_start;
     t->range_end = range_end;
     t->to_state = to_state;
@@ -266,7 +283,7 @@ yaz_nfa_state *yaz_nfa_add_sequence(yaz_nfa *n,
 struct matcher {
     yaz_nfa *n; 
     yaz_nfa_char *longest;
-    int bestnode;
+    int bestnode; 
     void *result;
     int errorcode;
     int empties; /* count how many consecutive empty transitions */
@@ -278,14 +295,15 @@ struct matcher {
 
 static void match_state(
               yaz_nfa_state *s, 
-              yaz_nfa_char *inchar,
-              size_t incharsleft,
-              struct matcher *m ) {
+              yaz_nfa_char *prevmatch,
+              yaz_nfa_char *inchar,   
+              size_t incharsleft,    
+              struct matcher *m ) {   
     yaz_nfa_transition *t = s->lasttrans;
     if (s->backref_start) 
         m->n->curr_backrefs[s->backref_start].start = inchar;
     if (s->backref_end) 
-        m->n->curr_backrefs[s->backref_end].end = inchar;
+        m->n->curr_backrefs[s->backref_end].end = prevmatch;
     if (t) {
         if (incharsleft) {
             do {
@@ -297,14 +315,15 @@ static void match_state(
                         m->n->curr_backrefs[0].start = inchar;
                         m->n->curr_backrefs[0].end = inchar;
                     }
-                    match_state(t->to_state, inchar+1, incharsleft-1, m);
-                    /* yes, descent to all matching nodes, even if overrun, */
-                    /* since we can find a better one later */
-                } else if (( t->range_start==EMPTY_START) && (t->range_end==EMPTY_END)) {
+                    match_state(t->to_state, inchar, 
+                            inchar+1, incharsleft-1, m);
+                } else if (( t->range_start==EMPTY_START) && 
+                           (t->range_end==EMPTY_END)) {
                     if ( m->empties++ > LOOP_LIMIT ) 
                         m->errorcode= YAZ_NFA_LOOP;
                     else
-                        match_state(t->to_state, inchar, incharsleft, m);
+                        match_state(t->to_state, prevmatch, 
+                                inchar, incharsleft, m);
                 }
             } while (t != s->lasttrans );
         } else {
@@ -335,7 +354,7 @@ static void match_state(
 
 int yaz_nfa_match(yaz_nfa *n, 
            yaz_nfa_char **inbuff, 
-           size_t incharsleft,
+           size_t *incharsleft,
            void **result ){
     struct matcher m;
     int sz;
@@ -349,6 +368,7 @@ int yaz_nfa_match(yaz_nfa *n,
     m.bestnode = n->nstates;
     m.result = 0;
     m.errorcode = 0;
+    m.empties = 0;
     sz = sizeof( struct yaz_nfa_backref_info) * n->nbackrefs;
     if (!n->curr_backrefs) {
         n->curr_backrefs = nmem_malloc( n->nmem, sz);
@@ -361,8 +381,9 @@ int yaz_nfa_match(yaz_nfa *n,
         n->best_backrefs[i].end = 0;
     }
 
-    match_state(n->firststate, *inbuff, incharsleft, &m);
+    match_state(n->firststate, *inbuff, *inbuff, *incharsleft, &m);
     if (m.result) {
+        *incharsleft -= (m.longest-*inbuff);
         *result = m.result;
         *inbuff = m.longest;
         if (m.errorcode)
@@ -392,6 +413,151 @@ int yaz_nfa_get_backref( yaz_nfa *n,
     return 0;
 }
 
+/* * * * * * * * * * * * * *
+ * Converters 
+ * * * * * * * * * * * * * */
+
+static yaz_nfa_converter *create_null_converter ( yaz_nfa *n) {
+    yaz_nfa_converter *c;
+    c=nmem_malloc(n->nmem, sizeof(yaz_nfa_converter));
+    c->next=0;
+    c->type=conv_none;
+    c->string=0;
+    c->strlen=0;
+    c->backref_no=0;
+    c->char_diff=0;
+    return c;
+}
+
+yaz_nfa_converter *yaz_nfa_create_string_converter (
+                yaz_nfa *n,
+                yaz_nfa_char *string,
+                size_t length){
+    yaz_nfa_converter *c;
+    int i;
+    c=create_null_converter(n);
+    c->type=conv_string;
+    c->string=nmem_malloc(n->nmem, length*sizeof(yaz_nfa_char));
+    for (i=0;i<length;i++)
+        c->string[i]=string[i];
+    c->strlen=length;
+    return c;
+}
+
+yaz_nfa_converter *yaz_nfa_create_backref_converter (
+                   yaz_nfa *n, int backref_no ) {
+    yaz_nfa_converter *c;
+    c=create_null_converter(n);
+    c->type=conv_backref;
+    c->backref_no=backref_no;
+    return c;
+}
+
+yaz_nfa_converter *yaz_nfa_create_range_converter (
+                yaz_nfa *n, int backref_no,
+                yaz_nfa_char from_char,
+                yaz_nfa_char to_char){
+    yaz_nfa_converter *c;
+    c=create_null_converter(n);
+    c->type=conv_range;
+    c->backref_no=backref_no;
+    c->char_diff=to_char - from_char;
+    return c;
+    
+}
+
+
+void yaz_nfa_append_converter (
+                yaz_nfa *n,
+                yaz_nfa_converter *startpoint,
+                yaz_nfa_converter *newconverter) {
+    while (startpoint->next)
+        startpoint=startpoint->next;
+    startpoint->next=newconverter;
+}
+
+static int string_convert (
+                yaz_nfa *n,
+                yaz_nfa_converter *c,
+                yaz_nfa_char **outbuff,
+                size_t *outcharsleft){
+    size_t sz=c->strlen;
+    yaz_nfa_char *p=c->string;
+    while (sz--) {
+        if ((*outcharsleft)-- <= 0)
+            return 2;
+        **outbuff=*p++;
+        (*outbuff)++;
+    }
+    return 0;
+}
+static int backref_convert (
+                yaz_nfa *n,
+                yaz_nfa_converter *c,
+                yaz_nfa_char **outbuff,
+                size_t *outcharsleft){
+    yaz_nfa_char *cp1,*cp2;
+    int i;
+    i=yaz_nfa_get_backref(n,c->backref_no, &cp1, &cp2);
+    if (i==2) /* no backref, produce no output, that's ok */
+        return 0;
+    if (i==1) /* no match in dfa */
+        return 1; /* should not happen */
+    while (cp2>=cp1) {
+        if ((*outcharsleft)-- <= 0)
+            return 2;
+        **outbuff=*cp1++;
+        (*outbuff)++;
+    }
+    return 0;
+}
+
+static int range_convert (
+                yaz_nfa *n,
+                yaz_nfa_converter *c,
+                yaz_nfa_char **outbuff,
+                size_t *outcharsleft){
+    yaz_nfa_char *cp1,*cp2;
+    int i;
+    i = yaz_nfa_get_backref(n,c->backref_no, &cp1, &cp2);
+    if (i == 2) /* no backref, produce no output, not ok */
+        return 1; /* should not happen */
+    if (i == 1) /* no match in dfa */
+        return 1; /* should not happen */
+    while (cp2 >= cp1) {
+        if ((*outcharsleft)-- <= 0)
+            return 2;
+        **outbuff=(*cp1++) + c->char_diff ;
+        (*outbuff)++;
+    }
+    return 0;
+}
+
+
+int yaz_nfa_run_converters(
+                yaz_nfa *n,
+                yaz_nfa_converter *c,
+                yaz_nfa_char **outbuff,
+                size_t *outcharsleft){
+    int rc=0;
+    while (c && !rc) {
+        switch(c->type) {
+            case conv_string:
+                rc=string_convert(n,c,outbuff,outcharsleft);
+                break;
+            case conv_backref:
+                rc=backref_convert(n,c,outbuff,outcharsleft);
+                break;
+            case conv_range:
+                rc=range_convert(n,c,outbuff,outcharsleft);
+                break;
+            default:
+                rc=3; /* internal error */
+        }
+        c=c->next;
+    }
+    return rc;
+}
 
 /* * * * * * * * *
  * Debug routines