json: improve parser reentrability

* include/grecs/json.h (jsonlex_cleanup): New proto.
* src/json-lex.l (jsonlex_setup): Initialize parser state.
Initialize json_current_locus_point.file to a non-NULL value.
(jsonlex_cleanup): New function.
* src/json-gram.y (json_parse_string): Call jsonlex_cleanup before returning.
* src/diag.c (default_print_diag): Print the passed errcode argument,
instead of errno.

3 files changed, 25 insertions, 13 deletions

diff --git a/src/diag.c b/src/diag.c
index bdbb407..db96e75 100644
--- a/src/diag.c
+++ b/src/diag.c
@@ -37,7 +37,7 @@ default_print_diag(grecs_locus_t const *locus, int err, int errcode,
                 fprintf(stderr, "warning: ");
         fprintf(stderr, "%s", msg);
         if (errcode)
-                fprintf(stderr, ": %s", strerror(errno));
+                fprintf(stderr, ": %s", strerror(errcode));
         fputc('\n', stderr);
 }
 
diff --git a/src/json-gram.y b/src/json-gram.y
index fe8996b..d5b0248 100644
--- a/src/json-gram.y
+++ b/src/json-gram.y
@@ -280,6 +280,7 @@ json_parse_string(char const *input, size_t len)
                 /* FIXME: error recovery */
                 return NULL;
         }
+        jsonlex_cleanup();
         return json_return_obj;
 }
 
diff --git a/src/json-lex.l b/src/json-lex.l
index 169cf32..4bbdedf 100644
--- a/src/json-lex.l
+++ b/src/json-lex.l
@@ -55,18 +55,6 @@ struct grecs_locus json_err_locus;
         } while (0);
 
 void
-jsonlex_setup(char const *s, size_t l)
-{
-        input_ptr = s;
-        input_size = l;
-        json_current_locus_point.file = NULL;
-        json_current_locus_point.line = 1;
-        json_current_locus_point.col = 0;
-        json_err_diag = NULL;
-        yy_flex_debug = 0;
-}
-
-void
 jsonlex_diag(const char *s)
 {
         if (!json_err_diag) {
@@ -227,3 +215,26 @@ false     { yylval.b = 0; return T_BOOL; }
 \n        grecs_locus_point_advance_line(json_current_locus_point);
 .         { jsonlex_diag("bogus character");
             return T_ERR; }
+%%
+void
+jsonlex_setup(char const *s, size_t l)
+{
+        input_ptr = s;
+        input_size = l;
+        json_current_locus_point.file = "input";
+        json_current_locus_point.line = 1;
+        json_current_locus_point.col = 0;
+        json_err_diag = NULL;
+        yy_flex_debug = 0;
+        BEGIN(INITIAL);
+        yyrestart(NULL);
+}
+
+void
+jsonlex_cleanup(void)
+{
+        if (json_line_acc) {
+                grecs_txtacc_free(json_line_acc);
+                json_line_acc = NULL;
+        }
+}