Add serd_new_float() and serd_new_double()

6 files changed, 63 insertions, 1 deletions

diff --git a/NEWS b/NEWS
index d900e544..2b792055 100644
--- a/NEWS
+++ b/NEWS
@@ -1,6 +1,7 @@
 serd (1.0.1) unstable;
 
   * Add SerdBuffer for mutable buffers to keep SerdChunk const-correct
+  * Add support for xsd:float and xsd:double literals
   * Bring read/write interface closer to C standard
   * Make nodes opaque
   * Remove serd_uri_to_path()
diff --git a/include/serd/serd.h b/include/serd/serd.h
index fdae8ac7..e1a28fdf 100644
--- a/include/serd/serd.h
+++ b/include/serd/serd.h
@@ -627,7 +627,37 @@ SerdNode* SERD_ALLOCATED
 serd_new_decimal(double d, const SerdNode* SERD_NULLABLE datatype);
 
 /**
-   Create a new node by serialising `i` into an xsd:integer string.
+   Create a new node by serialising `d` into a normalised xsd:double string.
+
+   The returned node will always be in normalised scientific notation, like
+   "1.23E4", except for NaN and negative/positive infinity, which are "NaN",
+   "-INF", and "INF", respectively.
+
+   Uses the shortest possible representation that precisely describes `d`,
+   which has at most 17 significant digits (under 24 characters total).
+
+   @param d Double value to serialise.
+   @return A literal node with datatype xsd:double.
+*/
+SERD_API
+SerdNode* SERD_ALLOCATED
+serd_new_double(double d);
+
+/**
+   Create a new node by serialising `f` into a normalised xsd:float string.
+
+   Uses identical formatting to serd_new_double(), except with at most 9
+   significant digits (under 14 characters total).
+
+   @param f Float value to serialise.
+   @return A literal node with datatype xsd:float.
+*/
+SERD_API
+SerdNode* SERD_ALLOCATED
+serd_new_float(float f);
+
+/**
+   Create a new node by serialising `i` into an xsd:integer string
 
    @param i Integer value to serialise.
    @param datatype Datatype of node, or NULL for xsd:integer.
diff --git a/meson.build b/meson.build
index 98ae0d5e..4dd4b6e5 100644
--- a/meson.build
+++ b/meson.build
@@ -33,6 +33,7 @@ if get_option('strict')
       '-Wno-covered-switch-default',
       '-Wno-disabled-macro-expansion',
       '-Wno-double-promotion',
+      '-Wno-float-equal',
       '-Wno-format-nonliteral',
       '-Wno-implicit-fallthrough',
       '-Wno-nullability-extension',
diff --git a/src/node.c b/src/node.c
index 0d6eb19a..db183fc0 100644
--- a/src/node.c
+++ b/src/node.c
@@ -507,6 +507,32 @@ serd_new_custom_literal(const void* const     user_data,
   return node;
 }
 
+SerdNode*
+serd_new_double(const double d)
+{
+  char buf[EXESS_MAX_DOUBLE_LENGTH + 1] = {0};
+
+  const ExessResult r = exess_write_double(d, sizeof(buf), buf);
+
+  return r.status
+           ? NULL
+           : serd_new_typed_literal(SERD_STRING_VIEW(buf, r.count),
+                                    SERD_STATIC_STRING(EXESS_XSD_URI "double"));
+}
+
+SerdNode*
+serd_new_float(const float f)
+{
+  char buf[EXESS_MAX_FLOAT_LENGTH + 1] = {0};
+
+  const ExessResult r = exess_write_float(f, sizeof(buf), buf);
+
+  return r.status
+           ? NULL
+           : serd_new_typed_literal(SERD_STRING_VIEW(buf, r.count),
+                                    SERD_STATIC_STRING(EXESS_XSD_URI "float"));
+}
+
 static size_t
 write_variant_literal(const void* const user_data,
                       const size_t      buf_size,
diff --git a/src/static_nodes.h b/src/static_nodes.h
index 952c0634..adbb5849 100644
--- a/src/static_nodes.h
+++ b/src/static_nodes.h
@@ -34,6 +34,8 @@ typedef struct StaticNode {
 DEFINE_XSD_NODE(base64Binary)
 DEFINE_XSD_NODE(boolean)
 DEFINE_XSD_NODE(decimal)
+DEFINE_XSD_NODE(double)
+DEFINE_XSD_NODE(float)
 DEFINE_XSD_NODE(integer)
 
 #endif // SERD_STATIC_NODES_H
diff --git a/src/string.c b/src/string.c
index 00b1e91a..6e28778b 100644
--- a/src/string.c
+++ b/src/string.c
@@ -21,6 +21,8 @@
 
 #include <assert.h>
 #include <math.h>
+#include <stdbool.h>
+#include <stdint.h>
 #include <stdlib.h>
 #include <string.h>