1 files changed, 53 insertions, 2 deletions

diff --git a/pcilib/unit.c b/pcilib/unit.c
index 2dd7113..6817afc 100644
--- a/pcilib/unit.c
+++ b/pcilib/unit.c
@@ -9,16 +9,38 @@
 #include "error.h"
 
 
-pcilib_unit_t pcilib_find_unit_by_name(pcilib_t *ctx, const char *unit) {
+static pcilib_unit_transform_t pcilib_unit_transform_null = { NULL, NULL };
+
+pcilib_unit_t pcilib_find_unit_by_name(pcilib_t *ctx, const char *name) {
     pcilib_unit_t i;
 
     for(i = 0; ctx->units[i].name; i++) {
-        if (!strcasecmp(ctx->units[i].name, unit))
+        if (!strcasecmp(ctx->units[i].name, name))
 	    return i;
     }
     return PCILIB_UNIT_INVALID;
 }
 
+pcilib_unit_transform_t *pcilib_find_transform_by_unit_names(pcilib_t *ctx, const char *from, const char *to) {
+    int i;
+    pcilib_unit_t unit;
+
+    if ((!from)||(!to))
+	return NULL;
+
+    if (!strcasecmp(from, to)) 
+	return &pcilib_unit_transform_null;
+
+    unit = pcilib_find_unit_by_name(ctx, from);
+    if (unit == PCILIB_UNIT_INVALID) return NULL;
+
+    for (i = 0; ctx->units[unit].transforms[i].unit; i++) {
+        if (!strcasecmp(ctx->units[unit].transforms[i].unit, to))
+            return &ctx->units[unit].transforms[i];
+    }
+
+    return NULL;
+}
 
 int pcilib_add_units(pcilib_t *ctx, size_t n, const pcilib_unit_description_t *desc) {
     if (!n) {
@@ -47,3 +69,32 @@ int pcilib_add_units(pcilib_t *ctx, size_t n, const pcilib_unit_description_t *d
 
     return 0;
 }
+
+
+int pcilib_transform_unit(pcilib_t *ctx, pcilib_unit_transform_t *trans, pcilib_value_t *value) {
+    int err;
+
+    err = pcilib_py_eval_string(ctx, trans->transform, value);
+    if (err) return err;
+
+    value->unit = trans->unit;
+    return 0;
+}
+
+
+int pcilib_transform_unit_by_name(pcilib_t *ctx, const char *to, pcilib_value_t *value) {
+    pcilib_unit_transform_t *trans;
+
+    if (!value->unit) {
+        pcilib_warning("Can't transform unit of the value with unspecified unit");
+        return PCILIB_ERROR_INVALID_ARGUMENT;
+    }
+
+    trans = pcilib_find_transform_by_unit_names(ctx, value->unit, to);
+    if (!trans) {
+        pcilib_warning("Can't transform unit (%s) to (%s)", value->unit, to);
+        return PCILIB_ERROR_NOTSUPPORTED;
+    }
+
+    return pcilib_transform_unit(ctx, trans, value);
+}