Add memcmp(), clean up bochsrc.txt

kernel/libk/string.c

@@ -60,3 +60,16 @@ usize_t strlen(const char *str) {
   for (s = str; *s; ++s);
   return (s - str);
 }
+
+int memcmp(const void *s1, const void *s2, usize_t n) {
+  unsigned char *p = (unsigned char *)s1;
+  unsigned char *q = (unsigned char *)s2;
+
+  while (n--) {
+    if (*p != *q) {
+      return (int)*p - (int)*q;
+    }
+    p++, q++;
+  }
+  return 0;
+}

kernel/libk/string.h

@@ -36,6 +36,8 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 usize_t memset(void *dst, byte_t b, usize_t n);
 usize_t memcpy(void *dst, const void *src, usize_t n);
+int memcmp(const void *s1, const void *s2, usize_t n);
+
 void strncpy(char* dst, const char* src, usize_t n);
 usize_t strlen(const char *str);
 

platform/i386_pc/bochsrc.txt

@@ -1,22 +1,28 @@
 # machine
 megs: 64
 cpu: model=pentium
+
 # roms
 romimage: file=/usr/share/bochs/BIOS-bochs-latest, options=fastboot
 vgaromimage: file=/usr/share/bochs/VGABIOS-lgpl-latest.bin
+
 # device config
 ata0: enabled=1
 ata0-master: type=cdrom, path=out/i386_pc/mop3.iso, status=inserted
 com1: enabled=1, mode=file, dev=bochs-com1.log
+
 # clock
 clock: sync=realtime
+
 # boot device
 boot: cdrom
+
 # logging
 error: action=report
 panic: action=report
 info: action=report
 debug: action=ignore
 log: bochs.log
+
 # display
 display_library: x