X-Git-Url: http://git.indexdata.com/?p=yaz-moved-to-github.git;a=blobdiff_plain;f=src%2Fcqltransform.c;h=199425d8b08c2a04811d8c9ebb0f21328d956e18;hp=5cb26cb178d42388ba535e6e71dd7f422987d31f;hb=1f41a1d415d2ab138050a96020ed39caa0c4e323;hpb=e20eb836cfe0996588d259db1a57c80966795fd4

diff --git a/src/cqltransform.c b/src/cqltransform.c
index 5cb26cb..199425d 100644
--- a/src/cqltransform.c
+++ b/src/cqltransform.c
@@ -1,11 +1,7 @@
-/* $Id: cqltransform.c,v 1.27 2007-02-07 13:36:58 adam Exp $
-   Copyright (C) 1995-2007, Index Data ApS
-   Index Data Aps
-
-This file is part of the YAZ toolkit.
-
-See the file LICENSE.
-*/
+/* This file is part of the YAZ toolkit.
+ * Copyright (C) 1995-2008 Index Data
+ * See the file LICENSE for details.
+ */
 
 /**
  * \file cqltransform.c
@@ -28,6 +24,8 @@ See the file LICENSE.
 #include <yaz/cql.h>
 #include <yaz/xmalloc.h>
 #include <yaz/diagsrw.h>
+#include <yaz/tokenizer.h>
+#include <yaz/wrbuf.h>
 
 struct cql_prop_entry {
     char *pattern;
@@ -37,65 +35,85 @@ struct cql_prop_entry {
 
 struct cql_transform_t_ {
     struct cql_prop_entry *entry;
+    yaz_tok_cfg_t tok_cfg;
     int error;
     char *addinfo;
+    WRBUF w;
 };
 
 cql_transform_t cql_transform_open_FILE(FILE *f)
 {
     char line[1024];
-    cql_transform_t ct = (cql_transform_t) xmalloc (sizeof(*ct));
+    cql_transform_t ct = (cql_transform_t) xmalloc(sizeof(*ct));
     struct cql_prop_entry **pp = &ct->entry;
+    ct->tok_cfg = yaz_tok_cfg_create();
+    ct->w = wrbuf_alloc();
 
+    yaz_tok_cfg_single_tokens(ct->tok_cfg, "=");
     ct->error = 0;
     ct->addinfo = 0;
+
     while (fgets(line, sizeof(line)-1, f))
     {
-        const char *cp_value_start;
-        const char *cp_value_end;
-        const char *cp_pattern_start;
-        const char *cp_pattern_end;
-        const char *cp = line;
-
-        while (*cp && strchr(" \t", *cp))
-            cp++;
-        cp_pattern_start = cp;
-        
-        while (*cp && !strchr(" \t\r\n=#", *cp))
-            cp++;
-        cp_pattern_end = cp;
-        if (cp == cp_pattern_start)
-            continue;
-        while (*cp && strchr(" \t", *cp))
-            cp++;
-        if (*cp != '=')
+        yaz_tok_parse_t tp = yaz_tok_parse_buf(ct->tok_cfg, line);
+        int t;
+        wrbuf_rewind(ct->w);
+        t = yaz_tok_move(tp);
+        if (t == YAZ_TOK_STRING)
+        {
+            char * pattern = xstrdup(yaz_tok_parse_string(tp));
+            t = yaz_tok_move(tp);
+            if (t != '=')
+            {
+                yaz_tok_parse_destroy(tp);
+                cql_transform_close(ct);
+                return 0;
+            }
+            t = yaz_tok_move(tp);
+
+            while (t == YAZ_TOK_STRING)
+            {
+                /* attset type=value  OR  type=value */
+                wrbuf_puts(ct->w, yaz_tok_parse_string(tp));
+                t = yaz_tok_move(tp);
+                if (t == YAZ_TOK_EOF)
+                    break;
+                if (t == YAZ_TOK_STRING)  
+                {  
+                    wrbuf_puts(ct->w, " ");
+                    wrbuf_puts(ct->w, yaz_tok_parse_string(tp));
+                    t = yaz_tok_move(tp);
+                }
+                if (t != '=')
+                {
+                    yaz_tok_parse_destroy(tp);
+                    cql_transform_close(ct);
+                    return 0;
+                }
+                t = yaz_tok_move(tp);
+                if (t != YAZ_TOK_STRING) /* value */
+                {
+                    yaz_tok_parse_destroy(tp);
+                    cql_transform_close(ct);
+                    return 0;
+                }
+                wrbuf_puts(ct->w, "=");
+                wrbuf_puts(ct->w, yaz_tok_parse_string(tp));
+                t = yaz_tok_move(tp);
+                wrbuf_puts(ct->w, " ");
+            }
+            *pp = (struct cql_prop_entry *) xmalloc(sizeof(**pp));
+            (*pp)->pattern = pattern;
+            (*pp)->value = xstrdup(wrbuf_cstr(ct->w));
+            pp = &(*pp)->next;
+        }
+        else if (t != YAZ_TOK_EOF)
         {
-            *pp = 0;
+            yaz_tok_parse_destroy(tp);
             cql_transform_close(ct);
             return 0;
         }
-        cp++;
-        while (*cp && strchr(" \t\r\n", *cp))
-            cp++;
-        cp_value_start = cp;
-        cp_value_end = strchr(cp, '#');
-        if (!cp_value_end)
-            cp_value_end = strlen(line) + line;
-
-        if (cp_value_end != cp_value_start &&
-            strchr(" \t\r\n", cp_value_end[-1]))
-            cp_value_end--;
-        *pp = (struct cql_prop_entry *) xmalloc (sizeof(**pp));
-        (*pp)->pattern = (char *) xmalloc(cp_pattern_end-cp_pattern_start + 1);
-        memcpy ((*pp)->pattern, cp_pattern_start,
-                cp_pattern_end-cp_pattern_start);
-        (*pp)->pattern[cp_pattern_end-cp_pattern_start] = '\0';
-
-        (*pp)->value = (char *) xmalloc (cp_value_end-cp_value_start + 1);
-        if (cp_value_start != cp_value_end)
-            memcpy ((*pp)->value, cp_value_start, cp_value_end-cp_value_start);
-        (*pp)->value[cp_value_end - cp_value_start] = '\0';
-        pp = &(*pp)->next;
+        yaz_tok_parse_destroy(tp);
     }
     *pp = 0;
     return ct;
@@ -110,14 +128,15 @@ void cql_transform_close(cql_transform_t ct)
     while (pe)
     {
         struct cql_prop_entry *pe_next = pe->next;
-        xfree (pe->pattern);
-        xfree (pe->value);
-        xfree (pe);
+        xfree(pe->pattern);
+        xfree(pe->value);
+        xfree(pe);
         pe = pe_next;
     }
-    if (ct->addinfo)
-        xfree (ct->addinfo);
-    xfree (ct);
+    xfree(ct->addinfo);
+    yaz_tok_cfg_destroy(ct->tok_cfg);
+    wrbuf_destroy(ct->w);
+    xfree(ct);
 }
 
 cql_transform_t cql_transform_open_fname(const char *fname)
@@ -139,13 +158,13 @@ static const char *cql_lookup_property(cql_transform_t ct,
     struct cql_prop_entry *e;
 
     if (pat1 && pat2 && pat3)
-        sprintf (pattern, "%.39s.%.39s.%.39s", pat1, pat2, pat3);
+        sprintf(pattern, "%.39s.%.39s.%.39s", pat1, pat2, pat3);
     else if (pat1 && pat2)
-        sprintf (pattern, "%.39s.%.39s", pat1, pat2);
+        sprintf(pattern, "%.39s.%.39s", pat1, pat2);
     else if (pat1 && pat3)
-        sprintf (pattern, "%.39s.%.39s", pat1, pat3);
+        sprintf(pattern, "%.39s.%.39s", pat1, pat3);
     else if (pat1)
-        sprintf (pattern, "%.39s", pat1);
+        sprintf(pattern, "%.39s", pat1);
     else
         return 0;
     
@@ -185,6 +204,18 @@ int cql_pr_attr_uri(cql_transform_t ct, const char *category,
     {
         if (!res)
             res = cql_lookup_property(ct, category, prefix, eval);
+        /* we have some aliases for some relations unfortunately.. */
+        if (!res && !prefix && !strcmp(category, "relation"))
+        {
+            if (!strcmp(val, "=="))
+                res = cql_lookup_property(ct, category, prefix, "exact");
+            if (!strcmp(val, "="))
+                res = cql_lookup_property(ct, category, prefix, "eq");
+            if (!strcmp(val, "<="))
+                res = cql_lookup_property(ct, category, prefix, "le");
+            if (!strcmp(val, ">="))
+                res = cql_lookup_property(ct, category, prefix, "ge");
+        }
         if (!res)
             res = cql_lookup_property(ct, category, prefix, "*");
     }
@@ -200,7 +231,7 @@ int cql_pr_attr_uri(cql_transform_t ct, const char *category,
                 cp1++;
             if (cp1 - cp0 >= sizeof(buf))
                 break;
-            memcpy (buf, cp0, cp1 - cp0);
+            memcpy(buf, cp0, cp1 - cp0);
             buf[cp1-cp0] = 0;
             (*pr)("@attr ", client_data);
 
@@ -246,9 +277,9 @@ int cql_pr_attr(cql_transform_t ct, const char *category,
 }
 
 
-static void cql_pr_int (int val,
-                        void (*pr)(const char *buf, void *client_data),
-                        void *client_data)
+static void cql_pr_int(int val,
+                       void (*pr)(const char *buf, void *client_data),
+                       void *client_data)
 {
     char buf[21];              /* enough characters to 2^64 */
     sprintf(buf, "%d", val);
@@ -268,55 +299,61 @@ static int cql_pr_prox(cql_transform_t ct, struct cql_node *mods,
     int proxrel = 2;            /* less than or equal */
     int unit = 2;               /* word */
 
-    while (mods != 0) {
-        char *name = mods->u.st.index;
-        char *term = mods->u.st.term;
-        char *relation = mods->u.st.relation;
+    while (mods)
+    {
+        const char *name = mods->u.st.index;
+        const char *term = mods->u.st.term;
+        const char *relation = mods->u.st.relation;
 
         if (!strcmp(name, "distance")) {
             distance = strtol(term, (char**) 0, 0);
             distance_defined = 1;
-            if (!strcmp(relation, "=")) {
+            if (!strcmp(relation, "="))
                 proxrel = 3;
-            } else if (!strcmp(relation, ">")) {
+            else if (!strcmp(relation, ">"))
                 proxrel = 5;
-            } else if (!strcmp(relation, "<")) {
+            else if (!strcmp(relation, "<"))
                 proxrel = 1;
-            } else if (!strcmp(relation, ">=")) {
+            else if (!strcmp(relation, ">=")) 
                 proxrel = 4;
-            } else if (!strcmp(relation, "<=")) {
+            else if (!strcmp(relation, "<="))
                 proxrel = 2;
-            } else if (!strcmp(relation, "<>")) {
+            else if (!strcmp(relation, "<>"))
                 proxrel = 6;
-            } else {
-                ct->error = 40; /* Unsupported proximity relation */
+            else 
+            {
+                ct->error = YAZ_SRW_UNSUPP_PROX_RELATION;
                 ct->addinfo = xstrdup(relation);
                 return 0;
             }
-        } else if (!strcmp(name, "ordered")) {
+        } 
+        else if (!strcmp(name, "ordered"))
             ordered = 1;
-        } else if (!strcmp(name, "unordered")) {
+        else if (!strcmp(name, "unordered"))
             ordered = 0;
-        } else if (!strcmp(name, "unit")) {
-            if (!strcmp(term, "word")) {
+        else if (!strcmp(name, "unit"))
+        {
+            if (!strcmp(term, "word"))
                 unit = 2;
-            } else if (!strcmp(term, "sentence")) {
+            else if (!strcmp(term, "sentence"))
                 unit = 3;
-            } else if (!strcmp(term, "paragraph")) {
+            else if (!strcmp(term, "paragraph"))
                 unit = 4;
-            } else if (!strcmp(term, "element")) {
+            else if (!strcmp(term, "element"))
                 unit = 8;
-            } else {
-                ct->error = 42; /* Unsupported proximity unit */
+            else 
+            {
+                ct->error = YAZ_SRW_UNSUPP_PROX_UNIT;
                 ct->addinfo = xstrdup(term);
                 return 0;
             }
-        } else {
-            ct->error = 46;     /* Unsupported boolean modifier */
+        } 
+        else 
+        {
+            ct->error = YAZ_SRW_UNSUPP_BOOLEAN_MODIFIER;
             ct->addinfo = xstrdup(name);
             return 0;
         }
-
         mods = mods->u.st.modifiers;
     }
 
@@ -337,19 +374,30 @@ static int cql_pr_prox(cql_transform_t ct, struct cql_node *mods,
  * characters starting at `term', or a null pointer of there are
  * none -- like memchr().
  */
-static const char *wcchar(const char *term, int length)
+static const char *wcchar(int start, const char *term, int length)
 {
-    const char *best = 0;
-    const char *current;
-    char *whichp;
-
-    for (whichp = "*?"; *whichp != '\0'; whichp++) {
-        current = (const char *) memchr(term, *whichp, length);
-        if (current != 0 && (best == 0 || current < best))
-            best = current;
+    while (length > 0)
+    {
+        if (start || term[-1] != '\\')
+            if (strchr("*?", *term))
+                return term;
+        term++;
+        length--;
+        start = 0;
     }
+    return 0;
+}
+
 
-    return best;
+/* ### checks for CQL relation-name rather than Type-1 attribute */
+static int has_modifier(struct cql_node *cn, const char *name) {
+    struct cql_node *mod;
+    for (mod = cn->u.st.modifiers; mod != 0; mod = mod->u.st.modifiers) {
+        if (!strcmp(mod->u.st.index, name))
+            return 1;
+    }
+
+    return 0;
 }
 
 
@@ -361,67 +409,74 @@ void emit_term(cql_transform_t ct,
 {
     int i;
     const char *ns = cn->u.st.index_uri;
+    int process_term = !has_modifier(cn, "regexp");
+    char *z3958_mem = 0;
 
     assert(cn->which == CQL_NODE_ST);
 
-    if (length > 0)
+    if (process_term && length > 0)
     {
         if (length > 1 && term[0] == '^' && term[length-1] == '^')
         {
             cql_pr_attr(ct, "position", "firstAndLast", 0,
-                        pr, client_data, 32);
+                        pr, client_data, YAZ_SRW_ANCHORING_CHAR_IN_UNSUPP_POSITION);
             term++;
             length -= 2;
         }
         else if (term[0] == '^')
         {
             cql_pr_attr(ct, "position", "first", 0,
-                        pr, client_data, 32);
+                        pr, client_data, YAZ_SRW_ANCHORING_CHAR_IN_UNSUPP_POSITION);
             term++;
             length--;
         }
         else if (term[length-1] == '^')
         {
             cql_pr_attr(ct, "position", "last", 0,
-                        pr, client_data, 32);
+                        pr, client_data, YAZ_SRW_ANCHORING_CHAR_IN_UNSUPP_POSITION);
             length--;
         }
         else
         {
             cql_pr_attr(ct, "position", "any", 0,
-                        pr, client_data, 32);
+                        pr, client_data, YAZ_SRW_ANCHORING_CHAR_IN_UNSUPP_POSITION);
         }
     }
 
-    if (length > 0)
+    if (process_term && length > 0)
     {
+        const char *first_wc = wcchar(1, term, length);
+        const char *second_wc = first_wc ?
+            wcchar(0, first_wc+1, length-(first_wc-term)-1) : 0;
+
         /* Check for well-known globbing patterns that represent
          * simple truncation attributes as expected by, for example,
          * Bath-compliant server.  If we find such a pattern but
          * there's no mapping for it, that's fine: we just use a
          * general pattern-matching attribute.
          */
-        if (length > 1 && term[0] == '*' && term[length-1] == '*' &&
-            wcchar(term+1, length-2) == 0 &&
-            cql_pr_attr(ct, "truncation", "both", 0,
-                        pr, client_data, 0)) {
+        if (first_wc == term && second_wc == term + length-1 
+            && *first_wc == '*' && *second_wc == '*' 
+            && cql_pr_attr(ct, "truncation", "both", 0, pr, client_data, 0)) 
+        {
             term++;
             length -= 2;
         }
-        else if (term[0] == '*' &&
-                 wcchar(term+1, length-1) == 0 &&
-                 cql_pr_attr(ct, "truncation", "left", 0,
-                             pr, client_data, 0)) {
+        else if (first_wc == term && second_wc == 0 && *first_wc == '*'
+                 && cql_pr_attr(ct, "truncation", "left", 0,
+                                pr, client_data, 0))
+        {
             term++;
             length--;
         }
-        else if (term[length-1] == '*' &&
-                 wcchar(term, length-1) == 0 &&
-                 cql_pr_attr(ct, "truncation", "right", 0,
-                             pr, client_data, 0)) {
+        else if (first_wc == term + length-1 && second_wc == 0
+                 && *first_wc == '*'
+                 && cql_pr_attr(ct, "truncation", "right", 0, 
+                                pr, client_data, 0))
+        {
             length--;
         }
-        else if (wcchar(term, length))
+        else if (first_wc)
         {
             /* We have one or more wildcard characters, but not in a
              * way that can be dealt with using only the standard
@@ -433,17 +488,22 @@ void emit_term(cql_transform_t ct,
              * supported".
              */
             int i;
-            char *mem;
             cql_pr_attr(ct, "truncation", "z3958", 0,
-                        pr, client_data, 28);
-            mem = (char *) xmalloc(length+1);
-            for (i = 0; i < length; i++) {
-                if (term[i] == '*')      mem[i] = '?';
-                else if (term[i] == '?') mem[i] = '#';
-                else                     mem[i] = term[i];
+                        pr, client_data, YAZ_SRW_MASKING_CHAR_UNSUPP);
+            z3958_mem = (char *) xmalloc(length+1);
+            for (i = 0; i < length; i++)
+            {
+                if (i > 0 && term[i-1] == '\\')
+                    z3958_mem[i] = term[i];
+                else if (term[i] == '*')
+                    z3958_mem[i] = '?';
+                else if (term[i] == '?')
+                    z3958_mem[i] = '#';
+                else
+                    z3958_mem[i] = term[i];
             }
-            mem[length] = '\0';
-            term = mem;
+            z3958_mem[length] = '\0';
+            term = z3958_mem;
         }
         else {
             /* No masking characters.  Use "truncation.none" if given. */
@@ -454,7 +514,7 @@ void emit_term(cql_transform_t ct,
     if (ns) {
         cql_pr_attr_uri(ct, "index", ns,
                         cn->u.st.index, "serverChoice",
-                        pr, client_data, 16);
+                        pr, client_data, YAZ_SRW_UNSUPP_INDEX);
     }
     if (cn->u.st.modifiers)
     {
@@ -462,7 +522,7 @@ void emit_term(cql_transform_t ct,
         for (; mod; mod = mod->u.st.modifiers)
         {
             cql_pr_attr(ct, "relationModifier", mod->u.st.index, 0,
-                        pr, client_data, 20);
+                        pr, client_data, YAZ_SRW_UNSUPP_RELATION_MODIFIER);
         }
     }
 
@@ -470,22 +530,44 @@ void emit_term(cql_transform_t ct,
     for (i = 0; i<length; i++)
     {
         /* pr(int) each character */
-        char buf[3];
-        const char *cp;
+        /* we do not need to deal with \-sequences because the
+           CQL and PQF terms have same \-format, bug #1988 */
+        char buf[2];
 
-        buf[1] = term[i];
-        buf[2] = 0;
-        /* do we have to escape this char? */
-        if (buf[1] == '"')
-        {
-            buf[0] = '\\';
-            cp = buf;
-        }
-        else
-            cp = buf+1;
-        (*pr)(cp, client_data);
+        buf[0] = term[i];
+        buf[1] = '\0';
+        (*pr)(buf, client_data);
     }
     (*pr)("\" ", client_data);
+    xfree(z3958_mem);
+}
+
+void emit_terms(cql_transform_t ct,
+                struct cql_node *cn,
+                void (*pr)(const char *buf, void *client_data),
+                void *client_data,
+                const char *op)
+{
+    struct cql_node *ne = cn->u.st.extra_terms;
+    if (ne)
+    {
+        (*pr)("@", client_data);
+        (*pr)(op, client_data);
+        (*pr)(" ", client_data);
+    }
+    emit_term(ct, cn, cn->u.st.term, strlen(cn->u.st.term),
+              pr, client_data);
+    for (; ne; ne = ne->u.st.extra_terms)
+    {
+        if (ne->u.st.extra_terms)
+        {
+            (*pr)("@", client_data);
+            (*pr)(op, client_data);
+            (*pr)(" ", client_data);
+        }            
+        emit_term(ct, cn, ne->u.st.term, strlen(ne->u.st.term),
+                  pr, client_data);
+    }
 }
 
 void emit_wordlist(cql_transform_t ct,
@@ -550,50 +632,36 @@ void cql_transform_r(cql_transform_t ct,
         {
             if (!ct->error)
             {
-                ct->error = 15;
+                ct->error = YAZ_SRW_UNSUPP_CONTEXT_SET;
                 ct->addinfo = 0;
             }
         }
         cql_pr_attr(ct, "always", 0, 0, pr, client_data, 0);
-        if (cn->u.st.relation && !cql_strcmp(cn->u.st.relation, "="))
-            cql_pr_attr(ct, "relation", "eq", "scr",
-                        pr, client_data, 19);
-        else if (cn->u.st.relation && !cql_strcmp(cn->u.st.relation, "<="))
-            cql_pr_attr(ct, "relation", "le", "scr",
-                        pr, client_data, 19);
-        else if (cn->u.st.relation && !cql_strcmp(cn->u.st.relation, ">="))
-            cql_pr_attr(ct, "relation", "ge", "scr",
-                        pr, client_data, 19);
-        else
-            cql_pr_attr(ct, "relation", cn->u.st.relation, "eq",
-                        pr, client_data, 19);
+        cql_pr_attr(ct, "relation", cn->u.st.relation, 0, pr, client_data,
+                    YAZ_SRW_UNSUPP_RELATION);
         cql_pr_attr(ct, "structure", cn->u.st.relation, 0,
-                    pr, client_data, 24);
+                    pr, client_data, YAZ_SRW_UNSUPP_COMBI_OF_RELATION_AND_TERM);
         if (cn->u.st.relation && !cql_strcmp(cn->u.st.relation, "all"))
-        {
             emit_wordlist(ct, cn, pr, client_data, "and");
-        }
         else if (cn->u.st.relation && !cql_strcmp(cn->u.st.relation, "any"))
-        {
             emit_wordlist(ct, cn, pr, client_data, "or");
-        }
         else
-        {
-            emit_term(ct, cn, cn->u.st.term, strlen(cn->u.st.term),
-                      pr, client_data);
-        }
+            emit_terms(ct, cn, pr, client_data, "and");
         break;
     case CQL_NODE_BOOL:
         (*pr)("@", client_data);
         (*pr)(cn->u.boolean.value, client_data);
         (*pr)(" ", client_data);
         mods = cn->u.boolean.modifiers;
-        if (!strcmp(cn->u.boolean.value, "prox")) {
+        if (!strcmp(cn->u.boolean.value, "prox")) 
+        {
             if (!cql_pr_prox(ct, mods, pr, client_data))
                 return;
-        } else if (mods) {
+        } 
+        else if (mods)
+        {
             /* Boolean modifiers other than on proximity not supported */
-            ct->error = 46; /* SRW diag: "Unsupported boolean modifier" */
+            ct->error = YAZ_SRW_UNSUPP_BOOLEAN_MODIFIER;
             ct->addinfo = xstrdup(mods->u.st.index);
             return;
         }
@@ -608,8 +676,7 @@ void cql_transform_r(cql_transform_t ct,
     }
 }
 
-int cql_transform(cql_transform_t ct,
-                  struct cql_node *cn,
+int cql_transform(cql_transform_t ct, struct cql_node *cn,
                   void (*pr)(const char *buf, void *client_data),
                   void *client_data)
 {
@@ -617,8 +684,7 @@ int cql_transform(cql_transform_t ct,
     NMEM nmem = nmem_create();
 
     ct->error = 0;
-    if (ct->addinfo)
-        xfree (ct->addinfo);
+    xfree(ct->addinfo);
     ct->addinfo = 0;
 
     for (e = ct->entry; e ; e = e->next)
@@ -628,7 +694,7 @@ int cql_transform(cql_transform_t ct,
         else if (!cql_strcmp(e->pattern, "set"))
             cql_apply_prefix(nmem, cn, 0, e->value);
     }
-    cql_transform_r (ct, cn, pr, client_data);
+    cql_transform_r(ct, cn, pr, client_data);
     nmem_destroy(nmem);
     return ct->error;
 }
@@ -639,8 +705,7 @@ int cql_transform_FILE(cql_transform_t ct, struct cql_node *cn, FILE *f)
     return cql_transform(ct, cn, cql_fputs, f);
 }
 
-int cql_transform_buf(cql_transform_t ct, struct cql_node *cn,
-                      char *out, int max)
+int cql_transform_buf(cql_transform_t ct, struct cql_node *cn, char *out, int max)
 {
     struct cql_buf_write_info info;
     int r;
@@ -669,6 +734,14 @@ int cql_transform_error(cql_transform_t ct, const char **addinfo)
     *addinfo = ct->addinfo;
     return ct->error;
 }
+
+void cql_transform_set_error(cql_transform_t ct, int error, const char *addinfo)
+{
+    xfree(ct->addinfo);
+    ct->addinfo = addinfo ? xstrdup(addinfo) : 0;
+    ct->error = error;
+}
+
 /*
  * Local variables:
  * c-basic-offset: 4