Add `stddef.h` and libc headers cleanup (#396)

* Move headers to include/libc

* stddef

* move math.h

* General cleanup

* move fabs, sqrtf and sqrt to math.h

* move alloca and assert

* whoops

8 files changed, 181 insertions, 0 deletions

diff --git a/include/libc/alloca.h b/include/libc/alloca.h
new file mode 100644
index 000000000..4e8720f7e
--- /dev/null
+++ b/include/libc/alloca.h
@@ -0,0 +1,7 @@
+#ifndef ALLOCA_H
+#define ALLOCA_H
+
+void* alloca(u32);
+#define alloca  __builtin_alloca
+
+#endif
diff --git a/include/libc/assert.h b/include/libc/assert.h
new file mode 100644
index 000000000..1bc72e314
--- /dev/null
+++ b/include/libc/assert.h
@@ -0,0 +1,4 @@
+#ifndef ASSERT_H
+#define ASSERT_H
+
+#endif
diff --git a/include/libc/math.h b/include/libc/math.h
new file mode 100644
index 000000000..c6756d959
--- /dev/null
+++ b/include/libc/math.h
@@ -0,0 +1,36 @@
+#ifndef MATH_H
+#define MATH_H
+
+#include "PR/ultratypes.h"
+
+#define M_PI 3.14159265358979323846f
+#define M_SQRT2 1.41421356237309504880f
+#define M_SQRT1_2 0.70710678118654752440f	/* 1/sqrt(2) */
+#define FLT_MAX 340282346638528859811704183484516925440.0f
+#define SHT_MAX 32767.0f
+#define SHT_MINV (1.0f / SHT_MAX)
+#define DEGTORAD(x) ((x) * (M_PI / 180.0f))
+
+typedef union {
+    f64 d;
+    struct {
+        u32 hi;
+        u32 lo;
+    } word;
+} du;
+
+typedef union {
+    u32 i;
+    f32 f;
+} fu;
+
+extern f32 __libm_qnan_f;
+
+float fabsf(float f);
+#pragma intrinsic(fabsf)
+float sqrtf(float f);
+#pragma intrinsic(sqrtf)
+double sqrt(double d);
+#pragma intrinsic(sqrt)
+
+#endif
diff --git a/include/libc/stdarg.h b/include/libc/stdarg.h
new file mode 100644
index 000000000..77b8b8866
--- /dev/null
+++ b/include/libc/stdarg.h
@@ -0,0 +1,46 @@
+#ifndef STDARG_H
+#define STDARG_H
+
+#include "ultra64.h"
+
+// When building with GCC, use the official vaarg macros to avoid warnings
+// and possibly bad codegen.
+#ifdef __GNUC__
+#define va_list __builtin_va_list
+#define va_start __builtin_va_start
+#define va_arg __builtin_va_arg
+#define va_end __builtin_va_end
+#else
+
+typedef char *va_list;
+#define _FP 1
+#define _INT 0
+#define _STRUCT 2
+
+#define _VA_FP_SAVE_AREA 0x10
+#define _VA_ALIGN(p, a) (((unsigned int)(((char *)p) + ((a) > 4 ? (a) : 4) - 1)) & -((a) > 4 ? (a) : 4))
+#define va_start(vp, parmN) (vp = ((va_list)&parmN + sizeof(parmN)))
+
+#define __va_stack_arg(list, mode)                          \
+    (                                                       \
+        ((list) = (char *)_VA_ALIGN(list, __builtin_alignof(mode)) + \
+                  _VA_ALIGN(sizeof(mode), 4)),              \
+        (((char *)list) - (_VA_ALIGN(sizeof(mode), 4) - sizeof(mode))))
+
+#define __va_double_arg(list, mode)                                                                    \
+    (                                                                                                  \
+        (((long)list & 0x1) /* 1 byte aligned? */                                                      \
+             ? (list = (char *)((long)list + 7), (char *)((long)list - 6 - _VA_FP_SAVE_AREA))          \
+             : (((long)list & 0x2) /* 2 byte aligned? */                                               \
+                    ? (list = (char *)((long)list + 10), (char *)((long)list - 24 - _VA_FP_SAVE_AREA)) \
+                    : __va_stack_arg(list, mode))))
+
+#define va_arg(list, mode) ((mode *)(((__builtin_classof(mode) == _FP &&          \
+                                       __builtin_alignof(mode) == sizeof(double)) \
+                                          ? __va_double_arg(list, mode)           \
+                                          : __va_stack_arg(list, mode))))[-1]
+#define va_end(__list)
+
+#endif /* __GNUC__ */
+
+#endif /* STDARG_H */
diff --git a/include/libc/stdbool.h b/include/libc/stdbool.h
new file mode 100644
index 000000000..d441054c1
--- /dev/null
+++ b/include/libc/stdbool.h
@@ -0,0 +1,14 @@
+#ifndef STDBOOL
+#define STDBOOL
+
+#define __bool_true_false_are_defined 1
+
+#ifndef __cplusplus
+
+#define bool    u32
+#define false   0
+#define true    1
+
+#endif /* __cplusplus */
+
+#endif /* STDBOOL */
diff --git a/include/libc/stddef.h b/include/libc/stddef.h
new file mode 100644
index 000000000..4f55e5725
--- /dev/null
+++ b/include/libc/stddef.h
@@ -0,0 +1,20 @@
+#ifndef STDDEF_H
+#define STDDEF_H
+
+#include "PR/ultratypes.h"
+
+typedef u32 size_t;
+
+typedef s32 ptrdiff_t;
+
+#ifndef NULL
+#define NULL (void*)0
+#endif
+
+#ifdef __GNUC__
+#define offsetof(structure, member) __builtin_offsetof (structure, member)
+#else
+#define offsetof(structure, member) ((size_t)&(((structure*)0)->member))
+#endif
+
+#endif /* STDDEF_H */
diff --git a/include/libc/stdint.h b/include/libc/stdint.h
new file mode 100644
index 000000000..1696615a7
--- /dev/null
+++ b/include/libc/stdint.h
@@ -0,0 +1,29 @@
+#ifndef STDINT_H
+#define STDINT_H
+
+#include "PR/ultratypes.h"
+
+typedef s32 intptr_t;
+typedef u32 uintptr_t;
+
+#define INT8_MIN    (-0x80)
+#define INT16_MIN   (-0x8000)
+#define INT32_MIN   (-0x80000000)
+#define INT64_MIN   (-0x8000000000000000)
+
+#define INT8_MAX    0x7f
+#define INT16_MAX   0x7fff
+#define INT32_MAX   0x7fffffff
+#define INT64_MAX   0x7fffffffffffffff
+
+#define UINT8_MAX   0xff
+#define UINT16_MAX  0xffff
+#define UINT32_MAX  0xffffffff
+#define UINT64_MAX  0xffffffffffffffff
+
+#define INTPTR_MIN  (-0x80000000)
+#define INTPTR_MAX  0x7fffffff
+#define UINTPTR_MAX 0xffffffff
+
+
+#endif /* STDINT_H */
diff --git a/include/libc/stdlib.h b/include/libc/stdlib.h
new file mode 100644
index 000000000..57d352a13
--- /dev/null
+++ b/include/libc/stdlib.h
@@ -0,0 +1,25 @@
+#ifndef STDLIB_H
+#define STDLIB_H
+
+#include "libc/stddef.h"
+
+typedef struct {
+    /* 0x0 */ int quot;
+    /* 0x4 */ int rem;
+} div_t;
+
+typedef struct {
+    /* 0x0 */ long quot;
+    /* 0x4 */ long rem;
+} ldiv_t;
+
+typedef struct {
+    /* 0x0 */ long long quot;
+    /* 0x8 */ long long rem;
+} lldiv_t;
+
+typedef int ssize_t;
+
+typedef long wchar_t;
+
+#endif /* STDLIB_H */