Beginnings of a upb compiler.

Makefile

@@ -5,13 +5,14 @@ CXX=g++
 CFLAGS=-std=c99
 CPPFLAGS=-O0 -Wall -Wextra -pedantic -g -DUPB_UNALIGNED_READS_OK -fomit-frame-pointer
 OBJ=upb_parse.o upb_table.o upb_msg.o upb_enum.o upb_context.o descriptor.o
-all: $(OBJ) test_table tests
+all: $(OBJ) test_table tests upbc
 clean:
 	rm -f *.o test_table tests
 
 libupb.a: $(OBJ)
 	ar rcs libupb.a $(OBJ)
 test_table: libupb.a
+upbc: libupb.a
 
 -include deps
 deps: *.c *.h

upbc.c

@@ -0,0 +1,86 @@
+/*
+ * upb - a minimalist implementation of protocol buffers.
+ *
+ * upbc is the upb compiler.
+ *
+ * Copyright (c) 2009 Joshua Haberman.  See LICENSE for details.
+ */
+
+#include <ctype.h>
+#include <inttypes.h>
+#include "descriptor.h"
+#include "upb_context.h"
+
+/* These are in-place string transformations that do not change the length of
+ * the string (and thus never need to re-allocate). */
+static void to_cident(struct upb_string str)
+{
+  for(uint32_t i = 0; i < str.byte_len; i++)
+    if(str.ptr[i] == '.' || str.ptr[i] == '/')
+      str.ptr[i] = '_';
+}
+
+static void to_preproc(struct upb_string str)
+{
+  to_cident(str);
+  for(uint32_t i = 0; i < str.byte_len; i++)
+    str.ptr[i] = toupper(str.ptr[i]);
+}
+
+/* The .h file defines structs for the types defined in the .proto file.  It
+ * also defines constants for the enum values.
+ *
+ * Assumes that d has been validated. */
+static void write_header(google_protobuf_FileDescriptorProto *d, FILE *stream)
+{
+  /* Header file prologue. */
+  fprintf(stream, "/* Auto-generated from " UPB_STRFMT ".  Do not edit. */\n\n",
+          UPB_STRARG(*d->name));
+  struct upb_string include_guard_name = upb_strdup(*d->name);
+  to_preproc(include_guard_name);
+  fprintf(stream, "#ifndef " UPB_STRFMT "\n", UPB_STRARG(include_guard_name));
+  fprintf(stream, "#define " UPB_STRFMT "\n\n", UPB_STRARG(include_guard_name));
+  fputs("#include <upb_msg.h>\n\n", stream);
+  fputs("#ifdef __cplusplus\n", stream);
+  fputs("extern \"C\" {\n", stream);
+  fputs("#endif\n\n", stream);
+
+  /* Enums. */
+  if(d->set_flags.has.enum_type) {
+    fprintf(stream, "/* Enums. */\n\n");
+    for(uint32_t i = 0; i < d->enum_type->len; i++) {  /* Foreach enum */
+      google_protobuf_EnumDescriptorProto *e = d->enum_type->elements[i];
+      struct upb_string enum_name = upb_strdup(*e->name);
+      to_cident(enum_name);
+      fprintf(stream, "typedef enum " UPB_STRFMT " {\n", UPB_STRARG(enum_name));
+      if(e->set_flags.has.value) {
+        for(uint32_t j = 0; j < e->value->len; j++) {  /* Foreach enum value. */
+          google_protobuf_EnumValueDescriptorProto *v = e->value->elements[i];
+          struct upb_string value_name = upb_strdup(*v->name);
+          to_preproc(value_name);
+          /* "  GOOGLE_PROTOBUF_FIELDDESCRIPTORPROTO_TYPE_UINT32 = 13," */
+          fprintf(stream, "  " UPB_STRFMT " = %" PRIu32,
+                  UPB_STRARG(value_name), v->number);
+          if(j != e->value->len-1) fputc(',', stream);
+          fputc('\n', stream);
+          upb_strfree(value_name);
+        }
+      }
+      fprintf(stream, "} " UPB_STRFMT ";\n\n", UPB_STRARG(enum_name));
+      upb_strfree(enum_name);
+    }
+  }
+
+  /* Epilogue. */
+  fputs("#ifdef __cplusplus\n", stream);
+  fputs("}  /* extern \"C\" */\n", stream);
+  fputs("#endif\n\n", stream);
+  fprintf(stream, "#endif  /* " UPB_STRFMT " */\n", UPB_STRARG(include_guard_name));
+  upb_strfree(include_guard_name);
+}
+
+int main()
+{
+  write_header(&google_protobuf_filedescriptor, stdout);
+}
+