stuff

include/zinnia/archctl.h

@@ -0,0 +1,29 @@
+#ifndef ZINNIA_ARCHCTL_H
+#define ZINNIA_ARCHCTL_H
+
+#include <zinnia/status.h>
+#include <zinnia/syscall_stubs.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef enum {
+    // Does nothing.
+    ZN_ARCHCTL_NONE = 0,
+    // On x86_64, sets the FSBASE MSR to the value.
+    ZN_ARCHCTL_SET_FSBASE = 1,
+    // On x86_64, sets the GSBASE MSR to the value.
+    ZN_ARCHCTL_SET_GSBASE = 2,
+} zn_archctl_t;
+
+// Performs an architecture-dependent operation identified by `op`.
+static inline zn_status_t zn_archctl(zn_archctl_t op, void* value) {
+    return zn_syscall2(op, value, ZN_SYSCALL_ARCHCTL);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/channel.h

@@ -0,0 +1,64 @@
+#ifndef ZINNIA_CHANNEL_H
+#define ZINNIA_CHANNEL_H
+
+#include <zinnia/handle.h>
+#include <zinnia/status.h>
+#include <zinnia/syscall_stubs.h>
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum zn_channel_flags {
+    ZN_CHANNEL_NONE = 0,
+};
+
+// Creates a new channel.
+static inline zn_status_t zn_channel_create(
+    enum zn_channel_flags flags,
+    zn_handle_t* endpoint0,
+    zn_handle_t* endpoint1
+) {
+    return zn_syscall3(flags, endpoint0, endpoint1, ZN_SYSCALL_CHANNEL_CREATE);
+}
+
+// Notifies the peer that there is new data available.
+// The kernel only copies the first `num_handles` handles and `num_bytes` bytes.
+static inline zn_status_t zn_channel_write(
+    zn_handle_t channel,
+    const zn_handle_t* handles,
+    const void* bytes,
+    size_t num_handles,
+    size_t num_bytes
+) {
+    return zn_syscall5(channel, handles, bytes, num_handles, num_bytes, ZN_SYSCALL_CHANNEL_WRITE);
+}
+
+// Waits for a new message to appear in the channel.
+static inline zn_status_t zn_channel_read(
+    zn_handle_t channel,
+    zn_handle_t* handles,
+    void* bytes,
+    size_t num_handles,
+    size_t num_bytes,
+    size_t* read_handles,
+    size_t* read_bytes
+) {
+    return zn_syscall7(
+        channel,
+        handles,
+        bytes,
+        num_handles,
+        num_bytes,
+        read_handles,
+        read_bytes,
+        ZN_SYSCALL_CHANNEL_READ
+    );
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/futex.h

@@ -0,0 +1,26 @@
+#ifndef ZINNIA_FUTEX_H
+#define ZINNIA_FUTEX_H
+
+#include <zinnia/status.h>
+#include <zinnia/syscall_stubs.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Blocks the calling thread if *addr == expected.
+// Returns immediately if the value at addr has changed.
+static inline zn_status_t zn_futex_wait(int* addr, int expected) {
+    return zn_syscall2(addr, expected, ZN_SYSCALL_FUTEX_WAIT);
+}
+
+// Wakes up to `count` threads waiting on the given futex address.
+static inline zn_status_t zn_futex_wake(int* addr, int count) {
+    return zn_syscall2(addr, count, ZN_SYSCALL_FUTEX_WAKE);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/handle.h

@@ -0,0 +1,45 @@
+#ifndef ZINNIA_HANDLE_H
+#define ZINNIA_HANDLE_H
+
+#include <zinnia/rights.h>
+#include <zinnia/status.h>
+#include <zinnia/syscall_stubs.h>
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// A generic object handle.
+typedef int32_t zn_handle_t;
+
+#define ZN_HANDLE_INVALID     ((zn_handle_t)(0))
+#define ZN_HANDLE_THIS_NS     ((zn_handle_t)(-1))
+#define ZN_HANDLE_THIS_VAS    ((zn_handle_t)(-2))
+#define ZN_HANDLE_THIS_THREAD ((zn_handle_t)(-3))
+#define ZN_HANDLE_ZERO_VMO    ((zn_handle_t)(-4))
+
+// Checks an object handle for validity.
+static inline zn_status_t zn_handle_validate(zn_handle_t handle) {
+    return zn_syscall1(handle, ZN_SYSCALL_HANDLE_VALIDATE);
+}
+
+// Drops an object handle.
+// All further references using this handle are invalid. The numerical value
+// may become valid again, but it is an error to keep using it.
+// The underlying object gets freed only once no other handle references it.
+static inline zn_status_t zn_handle_drop(zn_handle_t handle) {
+    return zn_syscall1(handle, ZN_SYSCALL_HANDLE_DROP);
+}
+
+// Creates a new handle pointing to the same object as pointed to
+// by the original handle. The new handle may obtain new rights.
+static inline zn_status_t zn_handle_clone(zn_handle_t handle, zn_rights_t cloned_rights, zn_handle_t* cloned) {
+    return zn_syscall3(handle, cloned_rights, cloned, ZN_SYSCALL_HANDLE_CLONE);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/ipc/init.h

@@ -0,0 +1,46 @@
+#pragma once
+
+#include <zinnia/handle.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#define IPC_GET_STRING(data, str, buf) \
+    do { \
+        memcpy(buf, (data) + (str)->offset, (str)->len); \
+    } while (0)
+
+#define IPC_SET_STRING(cursor, data, field, string) \
+    do { \
+        const size_t _len = strlen(string); \
+        (field)->offset = cursor; \
+        (field)->len = _len; \
+        memcpy(data + cursor, string, _len); \
+        cursor += _len; \
+    } while (0)
+
+enum ipc_msg_id {
+    IPC_MSG_FOO,
+    IPC_MSG_BAR,
+    IPC_MSG_BAZ,
+};
+
+struct ipc_array {
+    uint16_t offset;
+    uint16_t len;
+};
+
+struct ipc_option {
+    uint16_t offset;
+};
+
+struct ipc_init_register_rq {
+    enum ipc_msg_id id;
+    struct ipc_array name;
+    char data[];
+};
+
+struct ipc_kernel_msg {
+    enum ipc_msg_id id;
+    struct ipc_array name;
+    char data[];
+};

include/zinnia/mem.h

@@ -0,0 +1,64 @@
+#ifndef ZINNIA_MEM_H
+#define ZINNIA_MEM_H
+
+#include <zinnia/handle.h>
+#include <zinnia/status.h>
+#include <zinnia/syscall_stubs.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Virtual memory flags.
+enum zn_vm_flags {
+    // Mapping is readable.
+    ZN_VM_MAP_READ = 1 << 0,
+    // Mapping is writable.
+    ZN_VM_MAP_WRITE = 1 << 1,
+    // Mapping is executable.
+    ZN_VM_MAP_EXEC = 1 << 2,
+    // Shared memory (not cloned on calls to fork).
+    ZN_VM_MAP_SHARED = 1 << 3,
+
+    // Map at a fixed address, replacing whatever is in the way.
+    ZN_VM_MAP_FIXED = 1 << 8,
+    // Map at a fixed address, failing if anything is in the way.
+    ZB_VM_MAP_FIXED_NOREPLACE = 1 << 9,
+    // Map the entire range immediately.
+    ZN_VM_MAP_POPULATE = 1 << 10,
+};
+
+// Creates a new virtual memory object.
+static inline zn_status_t zn_vmo_create(size_t length, zn_handle_t* out) {
+    return zn_syscall2(length, out, ZN_SYSCALL_VMO_CREATE);
+}
+
+// Creates a new virtual memory object which points to a contiguous phyiscal memory region.
+static inline zn_status_t zn_vmo_create_phys(uintptr_t phys_addr, size_t length, zn_handle_t* out) {
+    return zn_syscall3(phys_addr, length, out, ZN_SYSCALL_VMO_CREATE_PHYS);
+}
+
+// Maps `bytes` of `vmo` at `vmo_offset` to `addr` in `vas`.
+static inline zn_status_t zn_vmo_map(
+    zn_handle_t vmo,
+    zn_handle_t vas,
+    uintptr_t vmo_offset,
+    uintptr_t* addr,
+    size_t bytes,
+    enum zn_vm_flags flags
+) {
+    return zn_syscall6(vmo, vas, vmo_offset, addr, bytes, flags, ZN_SYSCALL_VMO_MAP);
+}
+
+// Creates a new virtual address space.
+static inline zn_status_t zn_vas_create(zn_handle_t* out) {
+    return zn_syscall1(out, ZN_SYSCALL_VAS_CREATE);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/namespace.h

@@ -0,0 +1,24 @@
+#ifndef ZINNIA_NAMESPACE_H
+#define ZINNIA_NAMESPACE_H
+
+#include <zinnia/handle.h>
+#include <zinnia/status.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Creates a new namespace.
+static inline zn_status_t zn_ns_create(zn_handle_t* out) {
+    return ZN_ERR_UNSUPPORTED;
+}
+
+static inline zn_status_t zn_ns_move(zn_handle_t handle, zn_handle_t target_namespace) {
+    return ZN_ERR_UNSUPPORTED;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/random.h

@@ -0,0 +1,30 @@
+#ifndef ZINNIA_RANDOM_H
+#define ZINNIA_RANDOM_H
+
+#include <zinnia/status.h>
+#include <zinnia/syscall_stubs.h>
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum {
+    ZN_RANDOM_MAX_ENTROPY = 0x1000
+};
+
+// Stores random bytes in a buffer.
+static inline zn_status_t zn_random_get(void* addr, size_t len) {
+    return zn_syscall2(addr, len, ZN_SYSCALL_RANDOM_GET);
+}
+
+// Adds entropy to the RNG.
+static inline zn_status_t zn_random_entropy(const void* addr, size_t len) {
+    return zn_syscall2(addr, len, ZN_SYSCALL_RANDOM_ENTROPY);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/rights.h

@@ -0,0 +1,35 @@
+#ifndef ZINNIA_RIGHTS_H
+#define ZINNIA_RIGHTS_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef enum {
+    // Can be read from.
+    ZN_RIGHT_READ = 1u << 0,
+    // Can be written to.
+    ZN_RIGHT_WRITE = 1u << 1,
+    // Can be executed.
+    ZN_RIGHT_EXECUTE = 1u << 2,
+    // Can be mapped in an address space.
+    ZN_RIGHT_MAP = 1u << 3,
+    // Can be moved to another universe.
+    ZN_RIGHT_MOVE = 1u << 4,
+    // Can be cloned.
+    ZN_RIGHT_CLONE = 1u << 5,
+    // Can be deleted.
+    ZN_RIGHT_DELETE = 1u << 6,
+
+    // When cloning, use the same rights as the original.
+    ZN_RIGHTS_IDENTICAL = 1u << 31,
+    ZN_RIGHTS_COMMON = (ZN_RIGHT_MOVE | ZN_RIGHT_CLONE),
+    ZN_RIGHTS_RW = (ZN_RIGHT_READ | ZN_RIGHT_WRITE),
+    ZN_RIGHTS_ALL = ~0u,
+} zn_rights_t;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/status.h

@@ -0,0 +1,72 @@
+#ifndef ZINNIA_STATUS_H
+#define ZINNIA_STATUS_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Status values that may be returned by syscalls or other calls.
+// A status value of 0 means no error occured.
+// A negative value indicates a common error, usually from the kernel.
+typedef enum {
+    ZN_OK = 0,
+    // An internal error occured.
+    ZN_ERR_INTERNAL = -1,
+    // Syscall number is not a recognized syscall.
+    ZN_ERR_BAD_SYSCALL = -2,
+    // This operation is not supported or implemented yet.
+    ZN_ERR_UNSUPPORTED = -3,
+    // System does not have enough free memory for this operation.
+    ZN_ERR_NO_MEMORY = -4,
+    // Process can not own any more handles.
+    ZN_ERR_NO_HANDLES = -5,
+    // One or more of the provided arguments is not valid.
+    ZN_ERR_INVALID = -6,
+    // Argument is outside of the range for valid values.
+    ZN_ERR_BAD_RANGE = -7,
+    // Object handle does not name a valid object or correct type.
+    ZN_ERR_BAD_HANDLE = -8,
+    // Object has insufficient permissions for this operation.
+    ZN_ERR_BAD_PERMS = -9,
+    // Buffer is not large enough or doesn't point to a valid memory region.
+    ZN_ERR_BAD_BUFFER = -10,
+    // The resource already exists.
+    ZN_ERR_ALREADY_EXISTS = -11,
+} zn_status_t;
+
+static inline const char* zn_status_to_string(zn_status_t err) {
+    switch (err) {
+    case ZN_OK:
+        return "No error (OK)";
+    case ZN_ERR_INTERNAL:
+        return "An internal error occured (INTERNAL)";
+    case ZN_ERR_BAD_SYSCALL:
+        return "Syscall number is not a recognized syscall (BAD_SYSCALL)";
+    case ZN_ERR_UNSUPPORTED:
+        return "This operation is not supported or implemented yet (UNSUPPORTED)";
+    case ZN_ERR_NO_MEMORY:
+        return "System does not have enough free memory for this operation (NO_MEMORY)";
+    case ZN_ERR_NO_HANDLES:
+        return "Process can not own any more handles (NO_HANDLES)";
+    case ZN_ERR_INVALID:
+        return "One or more of the provided arguments is not valid (INVALID)";
+    case ZN_ERR_BAD_RANGE:
+        return "Argument is outside of the range for valid values (BAD_RANGE)";
+    case ZN_ERR_BAD_HANDLE:
+        return "Object handle does not name a valid object (BAD_HANDLE)";
+    case ZN_ERR_BAD_PERMS:
+        return "Object has insufficient permissions for this operation (BAD_PERMS)";
+    case ZN_ERR_BAD_BUFFER:
+        return "Buffer is not large enough or doesn't point to a valid memory region (BAD_BUFFER)";
+    case ZN_ERR_ALREADY_EXISTS:
+        return "The resource already exists (ALREADY_EXISTS)";
+    }
+
+    return "Unknown error code";
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/syscall_numbers.h

@@ -0,0 +1,36 @@
+#ifndef ZINNIA_SYSCALL_NUMBERS_H
+#define ZINNIA_SYSCALL_NUMBERS_H
+
+typedef enum {
+    ZN_SYSCALL_LOG,
+    ZN_SYSCALL_ARCHCTL,
+    ZN_SYSCALL_PAGE_SIZE,
+    ZN_SYSCALL_TIME,
+
+    ZN_SYSCALL_HANDLE_VALIDATE,
+    ZN_SYSCALL_HANDLE_DROP,
+    ZN_SYSCALL_HANDLE_CLONE,
+
+    ZN_SYSCALL_VAS_CREATE,
+
+    ZN_SYSCALL_VMO_CREATE,
+    ZN_SYSCALL_VMO_CREATE_PHYS,
+    ZN_SYSCALL_VMO_MAP,
+
+    ZN_SYSCALL_CHANNEL_CREATE,
+    ZN_SYSCALL_CHANNEL_WAIT,
+    ZN_SYSCALL_CHANNEL_READ,
+    ZN_SYSCALL_CHANNEL_WRITE,
+
+    ZN_SYSCALL_THREAD_CREATE,
+    ZN_SYSCALL_THREAD_START,
+    ZN_SYSCALL_THREAD_EXIT,
+
+    ZN_SYSCALL_RANDOM_GET,
+    ZN_SYSCALL_RANDOM_ENTROPY,
+
+    ZN_SYSCALL_FUTEX_WAIT,
+    ZN_SYSCALL_FUTEX_WAKE,
+} zn_syscall_t;
+
+#endif

include/zinnia/syscall_stubs.h

@@ -0,0 +1,252 @@
+#ifndef ZINNIA_SYSCALL_STUBS_H
+#define ZINNIA_SYSCALL_STUBS_H
+
+#include <zinnia/status.h>
+#include <zinnia/syscall_numbers.h>
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __x86_64__
+typedef uint64_t zn_arg_t;
+#elif defined(__aarch64__)
+typedef uint64_t zn_arg_t;
+#elif defined(__riscv) && (__riscv_xlen == 64)
+typedef uint64_t zn_arg_t;
+#elif defined(__loongarch64)
+typedef uint64_t zn_arg_t;
+#else
+#error "Unsupported architecture!"
+#endif
+
+#ifdef __x86_64__
+#define ASM_REG_NUM "rax"
+#define ASM_REG_RET "rax"
+#define ASM_REG_A0  "rdi"
+#define ASM_REG_A1  "rsi"
+#define ASM_REG_A2  "rdx"
+#define ASM_REG_A3  "r9"
+#define ASM_REG_A4  "r8"
+#define ASM_REG_A5  "r10"
+#define ASM_REG_A6  "r12"
+#define ASM_REG_A7  "r13"
+#define ASM_SYSCALL "syscall"
+#define ASM_CLOBBER "rcx", "r11"
+#elif defined(__aarch64__)
+#define ASM_REG_NUM "x8"
+#define ASM_REG_RET "x0"
+#define ASM_REG_A0  "x0"
+#define ASM_REG_A1  "x1"
+#define ASM_REG_A2  "x2"
+#define ASM_REG_A3  "x3"
+#define ASM_REG_A4  "x4"
+#define ASM_REG_A5  "x5"
+#define ASM_REG_A6  "x6"
+#define ASM_REG_A7  "x7"
+#define ASM_SYSCALL "svc 0"
+#define ASM_CLOBBER
+#elif defined(__riscv) && (__riscv_xlen == 64)
+#define ASM_REG_NUM "t3"
+#define ASM_REG_RET "a0"
+#define ASM_REG_A0  "a0"
+#define ASM_REG_A1  "a1"
+#define ASM_REG_A2  "a2"
+#define ASM_REG_A3  "a3"
+#define ASM_REG_A4  "a4"
+#define ASM_REG_A5  "a5"
+#define ASM_REG_A5  "a6"
+#define ASM_REG_A5  "a7"
+#define ASM_SYSCALL "ecall"
+#define ASM_CLOBBER
+#elif defined(__loongarch64)
+#define ASM_REG_NUM "a7"
+#define ASM_REG_RET "a0"
+#define ASM_REG_A0  "a0"
+#define ASM_REG_A1  "a1"
+#define ASM_REG_A2  "a2"
+#define ASM_REG_A3  "a3"
+#define ASM_REG_A4  "a4"
+#define ASM_REG_A5  "a5"
+// TODO: Define ABI
+#define ASM_REG_A6  TODO
+#define ASM_REG_A7  TODO
+#define ASM_SYSCALL "syscall 0"
+#define ASM_CLOBBER
+#else
+#error "Unsupported architecture!"
+#endif
+
+static inline zn_status_t zn_syscall0(zn_syscall_t num) {
+    register zn_syscall_t rnum asm(ASM_REG_NUM) = num;
+    register zn_status_t value asm(ASM_REG_RET);
+    asm volatile(ASM_SYSCALL : "=r"(value) : "r"(rnum) : "memory", ASM_CLOBBER);
+    return value;
+}
+
+static inline zn_status_t zn_syscall1(zn_arg_t a0, zn_syscall_t num) {
+    register zn_syscall_t rnum asm(ASM_REG_NUM) = num;
+    register zn_status_t value asm(ASM_REG_RET);
+    register zn_arg_t r0 asm(ASM_REG_A0) = a0;
+    asm volatile(ASM_SYSCALL : "=r"(value) : "r"(rnum), "r"(r0) : "memory", ASM_CLOBBER);
+    return value;
+}
+#define zn_syscall1(a0, num) zn_syscall1((zn_arg_t)a0, num)
+
+static inline zn_status_t zn_syscall2(zn_arg_t a0, zn_arg_t a1, zn_syscall_t num) {
+    register zn_syscall_t rnum asm(ASM_REG_NUM) = num;
+    register zn_status_t value asm(ASM_REG_RET);
+    register zn_arg_t r0 asm(ASM_REG_A0) = a0;
+    register zn_arg_t r1 asm(ASM_REG_A1) = a1;
+    asm volatile(ASM_SYSCALL : "=r"(value) : "r"(rnum), "r"(r0), "r"(r1) : "memory", ASM_CLOBBER);
+    return value;
+}
+#define zn_syscall2(a0, a1, num) zn_syscall2((zn_arg_t)a0, (zn_arg_t)a1, num)
+
+static inline zn_status_t zn_syscall3(zn_arg_t a0, zn_arg_t a1, zn_arg_t a2, zn_syscall_t num) {
+    register zn_syscall_t rnum asm(ASM_REG_NUM) = num;
+    register zn_status_t value asm(ASM_REG_RET);
+    register zn_arg_t r0 asm(ASM_REG_A0) = a0;
+    register zn_arg_t r1 asm(ASM_REG_A1) = a1;
+    register zn_arg_t r2 asm(ASM_REG_A2) = a2;
+    asm volatile(ASM_SYSCALL : "=r"(value) : "r"(rnum), "r"(r0), "r"(r1), "r"(r2) : "memory", ASM_CLOBBER);
+    return value;
+}
+#define zn_syscall3(a0, a1, a2, num) zn_syscall3((zn_arg_t)a0, (zn_arg_t)a1, (zn_arg_t)a2, num)
+
+static inline zn_status_t zn_syscall4(zn_arg_t a0, zn_arg_t a1, zn_arg_t a2, zn_arg_t a3, zn_syscall_t num) {
+    register zn_syscall_t rnum asm(ASM_REG_NUM) = num;
+    register zn_status_t value asm(ASM_REG_RET);
+    register zn_arg_t r0 asm(ASM_REG_A0) = a0;
+    register zn_arg_t r1 asm(ASM_REG_A1) = a1;
+    register zn_arg_t r2 asm(ASM_REG_A2) = a2;
+    register zn_arg_t r3 asm(ASM_REG_A3) = a3;
+    asm volatile(ASM_SYSCALL : "=r"(value) : "r"(rnum), "r"(r0), "r"(r1), "r"(r2), "r"(r3) : "memory", ASM_CLOBBER);
+    return value;
+}
+#define zn_syscall4(a0, a1, a2, a3, num) zn_syscall4((zn_arg_t)a0, (zn_arg_t)a1, (zn_arg_t)a2, (zn_arg_t)a3, num)
+
+static inline zn_status_t zn_syscall5(
+    zn_arg_t a0,
+    zn_arg_t a1,
+    zn_arg_t a2,
+    zn_arg_t a3,
+    zn_arg_t a4,
+    zn_syscall_t num
+) {
+    register zn_syscall_t rnum asm(ASM_REG_NUM) = num;
+    register zn_status_t value asm(ASM_REG_RET);
+    register zn_arg_t r0 asm(ASM_REG_A0) = a0;
+    register zn_arg_t r1 asm(ASM_REG_A1) = a1;
+    register zn_arg_t r2 asm(ASM_REG_A2) = a2;
+    register zn_arg_t r3 asm(ASM_REG_A3) = a3;
+    register zn_arg_t r4 asm(ASM_REG_A4) = a4;
+    asm volatile(ASM_SYSCALL
+                 : "=r"(value)
+                 : "r"(rnum), "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4)
+                 : "memory", ASM_CLOBBER);
+    return value;
+}
+#define zn_syscall5(a0, a1, a2, a3, a4, num) \
+    zn_syscall5((zn_arg_t)a0, (zn_arg_t)a1, (zn_arg_t)a2, (zn_arg_t)a3, (zn_arg_t)a4, num)
+
+static inline zn_status_t zn_syscall6(
+    zn_arg_t a0,
+    zn_arg_t a1,
+    zn_arg_t a2,
+    zn_arg_t a3,
+    zn_arg_t a4,
+    zn_arg_t a5,
+    zn_syscall_t num
+) {
+    register zn_syscall_t rnum asm(ASM_REG_NUM) = num;
+    register zn_status_t value asm(ASM_REG_RET);
+    register zn_arg_t r0 asm(ASM_REG_A0) = a0;
+    register zn_arg_t r1 asm(ASM_REG_A1) = a1;
+    register zn_arg_t r2 asm(ASM_REG_A2) = a2;
+    register zn_arg_t r3 asm(ASM_REG_A3) = a3;
+    register zn_arg_t r4 asm(ASM_REG_A4) = a4;
+    register zn_arg_t r5 asm(ASM_REG_A5) = a5;
+    asm volatile(ASM_SYSCALL
+                 : "=r"(value)
+                 : "r"(rnum), "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r5)
+                 : "memory", ASM_CLOBBER);
+    return value;
+}
+#define zn_syscall6(a0, a1, a2, a3, a4, a5, num) \
+    zn_syscall6((zn_arg_t)a0, (zn_arg_t)a1, (zn_arg_t)a2, (zn_arg_t)a3, (zn_arg_t)a4, (zn_arg_t)a5, num)
+
+static inline zn_status_t zn_syscall7(
+    zn_arg_t a0,
+    zn_arg_t a1,
+    zn_arg_t a2,
+    zn_arg_t a3,
+    zn_arg_t a4,
+    zn_arg_t a5,
+    zn_arg_t a6,
+    zn_syscall_t num
+) {
+    register zn_syscall_t rnum asm(ASM_REG_NUM) = num;
+    register zn_status_t value asm(ASM_REG_RET);
+    register zn_arg_t r0 asm(ASM_REG_A0) = a0;
+    register zn_arg_t r1 asm(ASM_REG_A1) = a1;
+    register zn_arg_t r2 asm(ASM_REG_A2) = a2;
+    register zn_arg_t r3 asm(ASM_REG_A3) = a3;
+    register zn_arg_t r4 asm(ASM_REG_A4) = a4;
+    register zn_arg_t r5 asm(ASM_REG_A5) = a5;
+    register zn_arg_t r6 asm(ASM_REG_A6) = a6;
+    asm volatile(ASM_SYSCALL
+                 : "=r"(value)
+                 : "r"(rnum), "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r5), "r"(r6)
+                 : "memory", ASM_CLOBBER);
+    return value;
+}
+#define zn_syscall7(a0, a1, a2, a3, a4, a5, a6, num) \
+    zn_syscall7((zn_arg_t)a0, (zn_arg_t)a1, (zn_arg_t)a2, (zn_arg_t)a3, (zn_arg_t)a4, (zn_arg_t)a5, (zn_arg_t)a6, num)
+
+static inline zn_status_t zn_syscall8(
+    zn_arg_t a0,
+    zn_arg_t a1,
+    zn_arg_t a2,
+    zn_arg_t a3,
+    zn_arg_t a4,
+    zn_arg_t a5,
+    zn_arg_t a6,
+    zn_arg_t a7,
+    zn_syscall_t num
+) {
+    register zn_syscall_t rnum asm(ASM_REG_NUM) = num;
+    register zn_status_t value asm(ASM_REG_RET);
+    register zn_arg_t r0 asm(ASM_REG_A0) = a0;
+    register zn_arg_t r1 asm(ASM_REG_A1) = a1;
+    register zn_arg_t r2 asm(ASM_REG_A2) = a2;
+    register zn_arg_t r3 asm(ASM_REG_A3) = a3;
+    register zn_arg_t r4 asm(ASM_REG_A4) = a4;
+    register zn_arg_t r5 asm(ASM_REG_A5) = a5;
+    register zn_arg_t r6 asm(ASM_REG_A6) = a6;
+    register zn_arg_t r7 asm(ASM_REG_A7) = a7;
+    asm volatile(ASM_SYSCALL
+                 : "=r"(value)
+                 : "r"(rnum), "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r5), "r"(r6), "r"(r7)
+                 : "memory", ASM_CLOBBER);
+    return value;
+}
+#define zn_syscall8(a0, a1, a2, a3, a4, a5, a6, a7, num) \
+    zn_syscall8( \
+        (zn_arg_t)a0, \
+        (zn_arg_t)a1, \
+        (zn_arg_t)a2, \
+        (zn_arg_t)a3, \
+        (zn_arg_t)a4, \
+        (zn_arg_t)a5, \
+        (zn_arg_t)a6, \
+        (zn_arg_t)a7, \
+        num \
+    )
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/system.h

@@ -0,0 +1,37 @@
+#ifndef ZINNIA_SYSTEM_H
+#define ZINNIA_SYSTEM_H
+
+#include <zinnia/status.h>
+#include <zinnia/syscall_stubs.h>
+#include <string.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+static inline void zn_log(const char* message, size_t len) {
+    zn_syscall2(message, len, ZN_SYSCALL_LOG);
+}
+
+// Returns the page size of the system.
+static inline size_t zn_page_size() {
+    size_t size = 0;
+    zn_syscall1(&size, ZN_SYSCALL_PAGE_SIZE);
+    return size;
+}
+
+static inline zn_status_t zn_powerctl() {
+    return ZN_ERR_UNSUPPORTED;
+}
+
+static inline uint64_t zn_time() {
+    uint64_t time = 0;
+    zn_syscall1(&time, ZN_SYSCALL_TIME);
+    return time;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

include/zinnia/thread.h

@@ -0,0 +1,43 @@
+#ifndef ZINNIA_THREAD_H
+#define ZINNIA_THREAD_H
+
+#include <zinnia/handle.h>
+#include <zinnia/status.h>
+#include <zinnia/syscall_stubs.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum zn_thread_flags {
+    ZN_THREAD_NONE = 0,
+};
+
+// Creates a new thread in the given namespace.
+static inline zn_status_t zn_thread_create(
+    zn_handle_t ns,
+    const char* name,
+    size_t name_len,
+    enum zn_thread_flags flags,
+    zn_handle_t* out
+) {
+    return zn_syscall5(ns, name, name_len, flags, out, ZN_SYSCALL_THREAD_CREATE);
+}
+
+// Starts executing a thread.
+static inline zn_status_t zn_thread_start(zn_handle_t thread, uintptr_t ip, uintptr_t sp, uintptr_t arg) {
+    return zn_syscall4(thread, ip, sp, arg, ZN_SYSCALL_THREAD_START);
+}
+
+// Stops execution of the calling thread.
+static inline void zn_thread_exit(void) {
+    zn_syscall0(ZN_SYSCALL_THREAD_EXIT);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif