Add spinlocks

Makefile

@@ -5,11 +5,13 @@ C_HEADERS = $(wildcard kernel/*.h kernel/cpu/$(PLAT)/*.h kernel/cpu/*.h kernel/t
 ASM = $(wildcard kernel/cpu/$(PLAT)/*.asm)
 S_ASM = $(wildcard kernel/cpu/$(PLAT)/*.s)
 LIBC_SOURCES = $(wildcard libc/*.c libc/*/*.c)
+LIBC_ASM_SOURCES = $(wildcard libc/*.asm libc/*/*.asm)
 LIBC_HEADERS = $(wildcard libc/*.h libc/*/*.h)
 OBJ = $(C_SOURCES:.c=.o kernel/cpu/$(PLAT)/boot.o)
 ASM_OBJ = $(S_ASM:.s=.o)
 S_ASM_OBJ = $(ASM:.asm=.o)
 LIBC_OBJ = $(LIBC_SOURCES:.c=.o)
+LIBC_ASM_OBJ = $(LIBC_ASM_SOURCES:.asm=.o)
 CC = $(shell cat psinfo/$(PLAT)/cc.txt)
 AS = $(shell cat psinfo/$(PLAT)/as.txt)
 AR = $(shell cat psinfo/$(PLAT)/ar.txt)
@@ -75,7 +77,7 @@ kernel/kernel.elf: $(OBJ) $(ASM_OBJ) $(S_ASM_OBJ) sysroot/usr/lib/libc.a
 
 libc: sysroot/usr/lib/libc.a
 
-sysroot/usr/lib/libc.a: $(LIBC_OBJ)
+sysroot/usr/lib/libc.a: $(LIBC_OBJ) $(LIBC_ASM_OBJ)
 	@$(AR) rcs $@ $^
 
 sysroot/usr/share/man: doc

libc/__helpers.asm

@@ -0,0 +1,9 @@
+global __pthread_spin_lock_helper
+
+__pthread_spin_lock_helper:
+  mov ebx,[esp+4]
+  mov eax,1
+  xchg eax,[ebx]
+  test eax, eax
+  jnz __pthread_spin_lock_helper
+  ret

libc/__helpers.h

@@ -0,0 +1,7 @@
+#ifndef __HELPERS_H
+#define __HELPERS_H
+#include <pthread.h>
+
+void __pthread_spin_lock_helper(pthread_spinlock_t* lock);
+
+#endif

libc/pthread.c

@@ -1,6 +1,7 @@
 #include <pthread.h>
 #include <stddef.h>
 #include <sys/syscalls.h>
+#include <__helpers.h>
 
 #define QUAUX(X) #X
 #define QU(X) QUAUX(X)
@@ -21,3 +22,22 @@ void pthread_exit(void *value_ptr) {
     mov $" QU(SYSCALL_THREAD_EXIT) ", %eax; \
     int $80;");
 }
+
+int pthread_spin_init(pthread_spinlock_t *lock, int pshared) {
+  *lock=0;
+  return 0;
+}
+
+int pthread_spin_lock(pthread_spinlock_t *lock) {
+  __pthread_spin_lock_helper(lock);
+  return 0;
+}
+
+int pthread_spin_unlock(pthread_spinlock_t *lock) {
+  *lock=0;
+  return 0;
+}
+
+int pthread_spin_destroy(pthread_spinlock_t *lock) {
+  return 0;
+}

libc/pthread.h

@@ -9,6 +9,7 @@
 
 typedef pid_t pthread_t; //!< Represents a thread
 typedef int pthread_attr_t; //!< Created as dummy
+typedef int pthread_spinlock_t; //!< Represents a spinlock
 
 /**
  * Create a thread in the current process
@@ -28,4 +29,35 @@ int pthread_create(pthread_t *restrict thread,
 */
 void pthread_exit(void *value_ptr);
 
+/**
+ * Initializes a spin lock
+ * \param lock The spinlock to initialize
+ * \param pshared Unused
+ * \returns 0 on success, 1 on failure
+*/
+int pthread_spin_init(pthread_spinlock_t *lock, int pshared);
+
+/**
+ * Locks a spin lock
+ * \param lock The spinlock to lock
+ * \returns 0 on success, 1 on failure
+*/
+int pthread_spin_lock(pthread_spinlock_t *lock);
+
+/**
+ * Unlocks a spin lock
+ * \param lock The spinlock to unlock
+ * \returns 0 on success, 1 on failure
+*/
+int pthread_spin_unlock(pthread_spinlock_t *lock);
+
+/**
+ * Destroys a spin lock
+ * \param lock The spinlock to destroy
+ * \returns 0 on success, 1 on failure
+*/
+int pthread_spin_destroy(pthread_spinlock_t *lock);
+
+
+
 #endif