add common lib
diff --git a/libasn1common/asn1_ref.c b/libasn1common/asn1_ref.c
new file mode 100644
index 0000000..a5ee998
--- /dev/null
+++ b/libasn1common/asn1_ref.c
@@ -0,0 +1,194 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+
+#include "asn1_ref.h"
+
+/*
+ * Construct a new empty reference.
+ */
+asn1p_ref_t *
+asn1p_ref_new(int _lineno, struct asn1p_module_s *mod) {
+ asn1p_ref_t *ref;
+
+ ref = calloc(1, sizeof *ref);
+ assert(ref);
+ asn1p_ref_set_source(ref, mod, _lineno);
+
+ return ref;
+}
+
+void
+asn1p_ref_free(asn1p_ref_t *ref) {
+ if(ref) {
+ if(ref->components) {
+ size_t i = ref->comp_count;
+ while(i--) {
+ free(ref->components[i].name);
+ ref->components[i].name = 0;
+ }
+ free(ref->components);
+ ref->components = 0;
+ }
+
+ free(ref);
+ }
+}
+
+void
+asn1p_ref_set_source(asn1p_ref_t *ref, struct asn1p_module_s *module,
+ int lineno) {
+ if(ref) {
+ ref->module = module;
+ ref->_lineno = lineno;
+ }
+}
+
+static enum asn1p_ref_lex_type_e
+asn1p_ref_name2lextype(const char *name) {
+ enum asn1p_ref_lex_type_e lex_type;
+ int has_lowercase = 0;
+
+ if(*name == '&') {
+ if(name[1] >= 'A' && name[1] <= 'Z') {
+ lex_type = RLT_AmpUppercase;
+ } else {
+ lex_type = RLT_Amplowercase;
+ }
+ } else if(*name >= 'A' && *name <= 'Z') {
+ const char *p;
+
+ for(p = name; *p; p++) {
+ if(*p >= 'a' && *p <= 'z') {
+ has_lowercase = 1;
+ break;
+ }
+ }
+
+ if(has_lowercase) {
+ lex_type = RLT_Uppercase;
+ } else {
+ lex_type = RLT_CAPITALS;
+ }
+ } else if(*name == '@') {
+ if(name[1] == '.')
+ lex_type = RLT_AtDotlowercase;
+ else
+ lex_type = RLT_Atlowercase;
+ } else {
+ lex_type = RLT_lowercase;
+ }
+
+ return lex_type;
+}
+
+int
+asn1p_ref_add_component(asn1p_ref_t *ref, const char *name, enum asn1p_ref_lex_type_e lex_type) {
+
+ if(!ref || !name
+ || (int)lex_type < RLT_UNKNOWN || lex_type >= RLT_MAX) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ if(ref->comp_count == ref->comp_size) {
+ int newsize = ref->comp_size?(ref->comp_size<<2):4;
+ void *p = realloc(ref->components,
+ newsize * sizeof(ref->components[0]));
+ if(p) {
+ ref->components = p;
+ ref->comp_size = newsize;
+ } else {
+ return -1;
+ }
+
+ }
+
+ if(lex_type == RLT_UNKNOWN) {
+ lex_type = asn1p_ref_name2lextype(name);
+ } else {
+ assert(lex_type == asn1p_ref_name2lextype(name));
+ }
+
+ ref->components[ref->comp_count].name = strdup(name);
+ ref->components[ref->comp_count].lex_type = lex_type;
+ if(ref->components[ref->comp_count].name) {
+ ref->comp_count++;
+ return 0;
+ } else {
+ return -1;
+ }
+}
+
+asn1p_ref_t *
+asn1p_ref_clone(asn1p_ref_t *ref) {
+ asn1p_ref_t *newref;
+
+ newref = asn1p_ref_new(ref->_lineno, ref->module);
+ if(newref) {
+ for(size_t i = 0; i < ref->comp_count; i++) {
+ if(asn1p_ref_add_component(newref,
+ ref->components[i].name,
+ ref->components[i].lex_type
+ )) {
+ asn1p_ref_free(newref);
+ newref = NULL;
+ break;
+ }
+ }
+ }
+
+ return newref;
+}
+
+int
+asn1p_ref_compare(const asn1p_ref_t *a, const asn1p_ref_t *b) {
+ if(a->comp_count != b->comp_count)
+ return -1;
+ if(a->module != b->module)
+ return -1;
+
+ for(size_t i = 0; i < a->comp_count; i++) {
+ if(a->components[i].lex_type != b->components[i].lex_type
+ || strcmp(a->components[i].name, b->components[i].name) != 0) {
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+const char *
+asn1p_ref_string(const asn1p_ref_t *ref) {
+ static char static_buf[32];
+ static char *buf = static_buf;
+ static size_t buf_size = sizeof(static_buf);
+ char *p = buf;
+
+ if(!ref) return "<no-ref>";
+
+ for(size_t i = 0; i < ref->comp_count; i++) {
+ size_t space = buf_size - (p - buf);
+ int ret =
+ snprintf(p, space, "%s%s", i ? "." : "", ref->components[i].name);
+ if(ret < 0 || (size_t)ret >= space) {
+ i--;
+ char *tmp = malloc(buf_size * 2 + 1);
+ assert(tmp);
+ size_t p_offset = p - buf;
+ memcpy(tmp, buf, (p - buf));
+ if(buf != static_buf) free(buf);
+ buf_size *= 2;
+ buf = tmp;
+ p = tmp + p_offset;
+ } else {
+ p += ret;
+ }
+ }
+
+ *p = '\0';
+ return buf;
+}
+