X-Git-Url: https://plomlompom.com/repos/foo.html?a=blobdiff_plain;f=src%2Freadwrite.c;h=039dadea4a6855e1f2222241193897db4f987b4c;hb=4d9b6ac142740aa337fc3e622902c9595c36f6d0;hp=449e96b4c3d5d5051e08d9d45a13864870ca9513;hpb=27cee0624f3dc430199c99f000179a3385e4d7c5;p=plomrogue
diff --git a/src/readwrite.c b/src/readwrite.c
index 449e96b..039dade 100644
--- a/src/readwrite.c
+++ b/src/readwrite.c
@@ -1,37 +1,103 @@
-/* readwrite.c */
+/* readwrite.c */
#include "readwrite.h"
-#include
-#include
+#include /* for FILE typedef*/
+#include /* for uint16_t, uint32_t */
-extern uint16_t read_uint16_bigendian( FILE * file )
+
+
+/* Read/write "x" from/to "file" as bigendian representation of "size" bits. */
+static uint8_t read_uintX_bigendian(FILE * file, uint32_t * x, uint8_t size);
+static uint8_t write_uintX_bigendian(FILE * file, uint32_t x, uint8_t size);
+
+
+
+static uint8_t read_uintX_bigendian(FILE * file, uint32_t * x, uint8_t size)
{
- uint16_t x;
- x = (uint16_t) fgetc(file) << 8;
- x = x + (uint16_t) fgetc(file);
- return x;
+ if (0 != size % 8)
+ {
+ return 1;
+ }
+ int16_t bitshift = size - 8;
+
+ * x = 0;
+ int test;
+ for (; bitshift >= 0; bitshift = bitshift - 8)
+ {
+ test = fgetc(file);
+ if (EOF == test)
+ {
+ return 1;
+ }
+ * x = * x + ((uint32_t) test << bitshift);
+ }
+ return 0;
}
-extern uint32_t read_uint32_bigendian( FILE * file )
+
+
+static uint8_t write_uintX_bigendian(FILE * file, uint32_t x, uint8_t size)
{
- uint32_t x;
- x = (uint32_t) fgetc(file) << 24;
- x = x + ( (uint32_t) fgetc(file) << 16 );
- x = x + ( (uint32_t) fgetc(file) << 8 );
- x = x + (uint32_t) fgetc(file);
- return x;
+ if (0 != size % 8)
+ {
+ return 1;
+ }
+ int16_t bitshift = size - 8;
+
+ for (; bitshift >= 0; bitshift = bitshift - 8)
+ {
+ if (EOF == fputc((x >> bitshift) & 0xFF, file))
+ {
+ return 1;
+ }
+ }
+ return 0;
}
-extern void write_uint16_bigendian( uint16_t x, FILE * file )
+
+
+extern uint8_t read_uint8(FILE * file, uint8_t * x)
+{
+ uint32_t y = * x;
+ uint8_t err = read_uintX_bigendian(file, &y, 8);
+ * x = (uint8_t) y;
+ return err;
+}
+
+
+
+extern uint8_t read_uint16_bigendian(FILE * file, uint16_t * x)
{
- fputc( x >> 8, file );
- fputc( x & 0xFF, file );
+ uint32_t y = * x;
+ uint8_t err = read_uintX_bigendian(file, &y, 16);
+ * x = (uint16_t) y;
+ return err;
}
-extern void write_uint32_bigendian( uint32_t x, FILE * file )
+
+
+extern uint8_t read_uint32_bigendian(FILE * file, uint32_t * x)
+{
+ return read_uintX_bigendian(file, x, 32);
+}
+
+
+
+extern uint8_t write_uint8(uint8_t x, FILE * file)
+{
+ return write_uintX_bigendian(file, x, 8);
+}
+
+
+
+extern uint8_t write_uint16_bigendian(uint16_t x, FILE * file)
+{
+ return write_uintX_bigendian(file, x, 16);
+}
+
+
+
+extern uint8_t write_uint32_bigendian(uint32_t x, FILE * file)
{
- fputc( x >> 24, file);
- fputc( ( x >> 16 ) & 0xFF, file);
- fputc( ( x >> 8 ) & 0xFF, file);
- fputc( x & 0xFF, file);
+ return write_uintX_bigendian(file, x, 32);
}