diff options
Diffstat (limited to 'tools/include/nolibc/nolibc.h')
| -rw-r--r-- | tools/include/nolibc/nolibc.h | 2540 |
1 files changed, 35 insertions, 2505 deletions
diff --git a/tools/include/nolibc/nolibc.h b/tools/include/nolibc/nolibc.h index c1c285fe494a..b2bc48d3cfe4 100644 --- a/tools/include/nolibc/nolibc.h +++ b/tools/include/nolibc/nolibc.h @@ -57,22 +57,32 @@ * having to specify anything. * * Finally some very common libc-level functions are provided. It is the case - * for a few functions usually found in string.h, ctype.h, or stdlib.h. Nothing - * is currently provided regarding stdio emulation. + * for a few functions usually found in string.h, ctype.h, or stdlib.h. * - * The macro NOLIBC is always defined, so that it is possible for a program to - * check this macro to know if it is being built against and decide to disable - * some features or simply not to include some standard libc files. - * - * Ideally this file should be split in multiple files for easier long term - * maintenance, but provided as a single file as it is now, it's quite - * convenient to use. Maybe some variations involving a set of includes at the - * top could work. + * The nolibc.h file is only a convenient entry point which includes all other + * files. It also defines the NOLIBC macro, so that it is possible for a + * program to check this macro to know if it is being built against and decide + * to disable some features or simply not to include some standard libc files. * * A simple static executable may be built this way : * $ gcc -fno-asynchronous-unwind-tables -fno-ident -s -Os -nostdlib \ * -static -include nolibc.h -o hello hello.c -lgcc * + * Simple programs meant to be reasonably portable to various libc and using + * only a few common includes, may also be built by simply making the include + * path point to the nolibc directory: + * $ gcc -fno-asynchronous-unwind-tables -fno-ident -s -Os -nostdlib \ + * -I../nolibc -o hello hello.c -lgcc + * + * The available standard (but limited) include files are: + * ctype.h, errno.h, signal.h, stdio.h, stdlib.h, string.h, time.h + * + * In addition, the following ones are expected to be provided by the compiler: + * float.h, stdarg.h, stddef.h + * + * The following ones which are part to the C standard are not provided: + * assert.h, locale.h, math.h, setjmp.h, limits.h + * * A very useful calling convention table may be found here : * http://man7.org/linux/man-pages/man2/syscall.2.html * @@ -80,2502 +90,22 @@ * https://w3challs.com/syscalls/ * */ +#ifndef _NOLIBC_H +#define _NOLIBC_H -#include <asm/unistd.h> -#include <asm/ioctls.h> -#include <asm/errno.h> -#include <linux/fs.h> -#include <linux/loop.h> -#include <linux/time.h> +#include "std.h" +#include "arch.h" +#include "types.h" +#include "sys.h" +#include "ctype.h" +#include "signal.h" +#include "stdio.h" +#include "stdlib.h" +#include "string.h" +#include "time.h" +#include "unistd.h" +/* Used by programs to avoid std includes */ #define NOLIBC -/* this way it will be removed if unused */ -static int errno; - -#ifndef NOLIBC_IGNORE_ERRNO -#define SET_ERRNO(v) do { errno = (v); } while (0) -#else -#define SET_ERRNO(v) do { } while (0) -#endif - -/* errno codes all ensure that they will not conflict with a valid pointer - * because they all correspond to the highest addressable memory page. - */ -#define MAX_ERRNO 4095 - -/* Declare a few quite common macros and types that usually are in stdlib.h, - * stdint.h, ctype.h, unistd.h and a few other common locations. - */ - -#define NULL ((void *)0) - -/* stdint types */ -typedef unsigned char uint8_t; -typedef signed char int8_t; -typedef unsigned short uint16_t; -typedef signed short int16_t; -typedef unsigned int uint32_t; -typedef signed int int32_t; -typedef unsigned long long uint64_t; -typedef signed long long int64_t; -typedef unsigned long size_t; -typedef signed long ssize_t; -typedef unsigned long uintptr_t; -typedef signed long intptr_t; -typedef signed long ptrdiff_t; - -/* for stat() */ -typedef unsigned int dev_t; -typedef unsigned long ino_t; -typedef unsigned int mode_t; -typedef signed int pid_t; -typedef unsigned int uid_t; -typedef unsigned int gid_t; -typedef unsigned long nlink_t; -typedef signed long off_t; -typedef signed long blksize_t; -typedef signed long blkcnt_t; -typedef signed long time_t; - -/* for poll() */ -struct pollfd { - int fd; - short int events; - short int revents; -}; - -/* for getdents64() */ -struct linux_dirent64 { - uint64_t d_ino; - int64_t d_off; - unsigned short d_reclen; - unsigned char d_type; - char d_name[]; -}; - -/* commonly an fd_set represents 256 FDs */ -#define FD_SETSIZE 256 -typedef struct { uint32_t fd32[FD_SETSIZE/32]; } fd_set; - -/* needed by wait4() */ -struct rusage { - struct timeval ru_utime; - struct timeval ru_stime; - long ru_maxrss; - long ru_ixrss; - long ru_idrss; - long ru_isrss; - long ru_minflt; - long ru_majflt; - long ru_nswap; - long ru_inblock; - long ru_oublock; - long ru_msgsnd; - long ru_msgrcv; - long ru_nsignals; - long ru_nvcsw; - long ru_nivcsw; -}; - -/* stat flags (WARNING, octal here) */ -#define S_IFDIR 0040000 -#define S_IFCHR 0020000 -#define S_IFBLK 0060000 -#define S_IFREG 0100000 -#define S_IFIFO 0010000 -#define S_IFLNK 0120000 -#define S_IFSOCK 0140000 -#define S_IFMT 0170000 - -#define S_ISDIR(mode) (((mode) & S_IFDIR) == S_IFDIR) -#define S_ISCHR(mode) (((mode) & S_IFCHR) == S_IFCHR) -#define S_ISBLK(mode) (((mode) & S_IFBLK) == S_IFBLK) -#define S_ISREG(mode) (((mode) & S_IFREG) == S_IFREG) -#define S_ISFIFO(mode) (((mode) & S_IFIFO) == S_IFIFO) -#define S_ISLNK(mode) (((mode) & S_IFLNK) == S_IFLNK) -#define S_ISSOCK(mode) (((mode) & S_IFSOCK) == S_IFSOCK) - -#define DT_UNKNOWN 0 -#define DT_FIFO 1 -#define DT_CHR 2 -#define DT_DIR 4 -#define DT_BLK 6 -#define DT_REG 8 -#define DT_LNK 10 -#define DT_SOCK 12 - -/* all the *at functions */ -#ifndef AT_FDCWD -#define AT_FDCWD -100 -#endif - -/* lseek */ -#define SEEK_SET 0 -#define SEEK_CUR 1 -#define SEEK_END 2 - -/* reboot */ -#define LINUX_REBOOT_MAGIC1 0xfee1dead -#define LINUX_REBOOT_MAGIC2 0x28121969 -#define LINUX_REBOOT_CMD_HALT 0xcdef0123 -#define LINUX_REBOOT_CMD_POWER_OFF 0x4321fedc -#define LINUX_REBOOT_CMD_RESTART 0x01234567 -#define LINUX_REBOOT_CMD_SW_SUSPEND 0xd000fce2 - - -/* The format of the struct as returned by the libc to the application, which - * significantly differs from the format returned by the stat() syscall flavours. - */ -struct stat { - dev_t st_dev; /* ID of device containing file */ - ino_t st_ino; /* inode number */ - mode_t st_mode; /* protection */ - nlink_t st_nlink; /* number of hard links */ - uid_t st_uid; /* user ID of owner */ - gid_t st_gid; /* group ID of owner */ - dev_t st_rdev; /* device ID (if special file) */ - off_t st_size; /* total size, in bytes */ - blksize_t st_blksize; /* blocksize for file system I/O */ - blkcnt_t st_blocks; /* number of 512B blocks allocated */ - time_t st_atime; /* time of last access */ - time_t st_mtime; /* time of last modification */ - time_t st_ctime; /* time of last status change */ -}; - -#define WEXITSTATUS(status) (((status) & 0xff00) >> 8) -#define WIFEXITED(status) (((status) & 0x7f) == 0) - -/* for SIGCHLD */ -#include <asm/signal.h> - -/* Below comes the architecture-specific code. For each architecture, we have - * the syscall declarations and the _start code definition. This is the only - * global part. On all architectures the kernel puts everything in the stack - * before jumping to _start just above us, without any return address (_start - * is not a function but an entry pint). So at the stack pointer we find argc. - * Then argv[] begins, and ends at the first NULL. Then we have envp which - * starts and ends with a NULL as well. So envp=argv+argc+1. - */ - -#if defined(__x86_64__) -/* Syscalls for x86_64 : - * - registers are 64-bit - * - syscall number is passed in rax - * - arguments are in rdi, rsi, rdx, r10, r8, r9 respectively - * - the system call is performed by calling the syscall instruction - * - syscall return comes in rax - * - rcx and r11 are clobbered, others are preserved. - * - the arguments are cast to long and assigned into the target registers - * which are then simply passed as registers to the asm code, so that we - * don't have to experience issues with register constraints. - * - the syscall number is always specified last in order to allow to force - * some registers before (gcc refuses a %-register at the last position). - * - see also x86-64 ABI section A.2 AMD64 Linux Kernel Conventions, A.2.1 - * Calling Conventions. - * - * Link x86-64 ABI: https://gitlab.com/x86-psABIs/x86-64-ABI/-/wikis/x86-64-psABI - * - */ - -#define my_syscall0(num) \ -({ \ - long _ret; \ - register long _num asm("rax") = (num); \ - \ - asm volatile ( \ - "syscall\n" \ - : "=a"(_ret) \ - : "0"(_num) \ - : "rcx", "r11", "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall1(num, arg1) \ -({ \ - long _ret; \ - register long _num asm("rax") = (num); \ - register long _arg1 asm("rdi") = (long)(arg1); \ - \ - asm volatile ( \ - "syscall\n" \ - : "=a"(_ret) \ - : "r"(_arg1), \ - "0"(_num) \ - : "rcx", "r11", "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall2(num, arg1, arg2) \ -({ \ - long _ret; \ - register long _num asm("rax") = (num); \ - register long _arg1 asm("rdi") = (long)(arg1); \ - register long _arg2 asm("rsi") = (long)(arg2); \ - \ - asm volatile ( \ - "syscall\n" \ - : "=a"(_ret) \ - : "r"(_arg1), "r"(_arg2), \ - "0"(_num) \ - : "rcx", "r11", "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall3(num, arg1, arg2, arg3) \ -({ \ - long _ret; \ - register long _num asm("rax") = (num); \ - register long _arg1 asm("rdi") = (long)(arg1); \ - register long _arg2 asm("rsi") = (long)(arg2); \ - register long _arg3 asm("rdx") = (long)(arg3); \ - \ - asm volatile ( \ - "syscall\n" \ - : "=a"(_ret) \ - : "r"(_arg1), "r"(_arg2), "r"(_arg3), \ - "0"(_num) \ - : "rcx", "r11", "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall4(num, arg1, arg2, arg3, arg4) \ -({ \ - long _ret; \ - register long _num asm("rax") = (num); \ - register long _arg1 asm("rdi") = (long)(arg1); \ - register long _arg2 asm("rsi") = (long)(arg2); \ - register long _arg3 asm("rdx") = (long)(arg3); \ - register long _arg4 asm("r10") = (long)(arg4); \ - \ - asm volatile ( \ - "syscall\n" \ - : "=a"(_ret) \ - : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), \ - "0"(_num) \ - : "rcx", "r11", "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall5(num, arg1, arg2, arg3, arg4, arg5) \ -({ \ - long _ret; \ - register long _num asm("rax") = (num); \ - register long _arg1 asm("rdi") = (long)(arg1); \ - register long _arg2 asm("rsi") = (long)(arg2); \ - register long _arg3 asm("rdx") = (long)(arg3); \ - register long _arg4 asm("r10") = (long)(arg4); \ - register long _arg5 asm("r8") = (long)(arg5); \ - \ - asm volatile ( \ - "syscall\n" \ - : "=a"(_ret) \ - : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \ - "0"(_num) \ - : "rcx", "r11", "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6) \ -({ \ - long _ret; \ - register long _num asm("rax") = (num); \ - register long _arg1 asm("rdi") = (long)(arg1); \ - register long _arg2 asm("rsi") = (long)(arg2); \ - register long _arg3 asm("rdx") = (long)(arg3); \ - register long _arg4 asm("r10") = (long)(arg4); \ - register long _arg5 asm("r8") = (long)(arg5); \ - register long _arg6 asm("r9") = (long)(arg6); \ - \ - asm volatile ( \ - "syscall\n" \ - : "=a"(_ret) \ - : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \ - "r"(_arg6), "0"(_num) \ - : "rcx", "r11", "memory", "cc" \ - ); \ - _ret; \ -}) - -/* startup code */ -/* - * x86-64 System V ABI mandates: - * 1) %rsp must be 16-byte aligned right before the function call. - * 2) The deepest stack frame should be zero (the %rbp). - * - */ -asm(".section .text\n" - ".global _start\n" - "_start:\n" - "pop %rdi\n" // argc (first arg, %rdi) - "mov %rsp, %rsi\n" // argv[] (second arg, %rsi) - "lea 8(%rsi,%rdi,8),%rdx\n" // then a NULL then envp (third arg, %rdx) - "xor %ebp, %ebp\n" // zero the stack frame - "and $-16, %rsp\n" // x86 ABI : esp must be 16-byte aligned before call - "call main\n" // main() returns the status code, we'll exit with it. - "mov %eax, %edi\n" // retrieve exit code (32 bit) - "mov $60, %eax\n" // NR_exit == 60 - "syscall\n" // really exit - "hlt\n" // ensure it does not return - ""); - -/* fcntl / open */ -#define O_RDONLY 0 -#define O_WRONLY 1 -#define O_RDWR 2 -#define O_CREAT 0x40 -#define O_EXCL 0x80 -#define O_NOCTTY 0x100 -#define O_TRUNC 0x200 -#define O_APPEND 0x400 -#define O_NONBLOCK 0x800 -#define O_DIRECTORY 0x10000 - -/* The struct returned by the stat() syscall, equivalent to stat64(). The - * syscall returns 116 bytes and stops in the middle of __unused. - */ -struct sys_stat_struct { - unsigned long st_dev; - unsigned long st_ino; - unsigned long st_nlink; - unsigned int st_mode; - unsigned int st_uid; - - unsigned int st_gid; - unsigned int __pad0; - unsigned long st_rdev; - long st_size; - long st_blksize; - - long st_blocks; - unsigned long st_atime; - unsigned long st_atime_nsec; - unsigned long st_mtime; - - unsigned long st_mtime_nsec; - unsigned long st_ctime; - unsigned long st_ctime_nsec; - long __unused[3]; -}; - -#elif defined(__i386__) || defined(__i486__) || defined(__i586__) || defined(__i686__) -/* Syscalls for i386 : - * - mostly similar to x86_64 - * - registers are 32-bit - * - syscall number is passed in eax - * - arguments are in ebx, ecx, edx, esi, edi, ebp respectively - * - all registers are preserved (except eax of course) - * - the system call is performed by calling int $0x80 - * - syscall return comes in eax - * - the arguments are cast to long and assigned into the target registers - * which are then simply passed as registers to the asm code, so that we - * don't have to experience issues with register constraints. - * - the syscall number is always specified last in order to allow to force - * some registers before (gcc refuses a %-register at the last position). - * - * Also, i386 supports the old_select syscall if newselect is not available - */ -#define __ARCH_WANT_SYS_OLD_SELECT - -#define my_syscall0(num) \ -({ \ - long _ret; \ - register long _num asm("eax") = (num); \ - \ - asm volatile ( \ - "int $0x80\n" \ - : "=a" (_ret) \ - : "0"(_num) \ - : "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall1(num, arg1) \ -({ \ - long _ret; \ - register long _num asm("eax") = (num); \ - register long _arg1 asm("ebx") = (long)(arg1); \ - \ - asm volatile ( \ - "int $0x80\n" \ - : "=a" (_ret) \ - : "r"(_arg1), \ - "0"(_num) \ - : "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall2(num, arg1, arg2) \ -({ \ - long _ret; \ - register long _num asm("eax") = (num); \ - register long _arg1 asm("ebx") = (long)(arg1); \ - register long _arg2 asm("ecx") = (long)(arg2); \ - \ - asm volatile ( \ - "int $0x80\n" \ - : "=a" (_ret) \ - : "r"(_arg1), "r"(_arg2), \ - "0"(_num) \ - : "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall3(num, arg1, arg2, arg3) \ -({ \ - long _ret; \ - register long _num asm("eax") = (num); \ - register long _arg1 asm("ebx") = (long)(arg1); \ - register long _arg2 asm("ecx") = (long)(arg2); \ - register long _arg3 asm("edx") = (long)(arg3); \ - \ - asm volatile ( \ - "int $0x80\n" \ - : "=a" (_ret) \ - : "r"(_arg1), "r"(_arg2), "r"(_arg3), \ - "0"(_num) \ - : "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall4(num, arg1, arg2, arg3, arg4) \ -({ \ - long _ret; \ - register long _num asm("eax") = (num); \ - register long _arg1 asm("ebx") = (long)(arg1); \ - register long _arg2 asm("ecx") = (long)(arg2); \ - register long _arg3 asm("edx") = (long)(arg3); \ - register long _arg4 asm("esi") = (long)(arg4); \ - \ - asm volatile ( \ - "int $0x80\n" \ - : "=a" (_ret) \ - : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), \ - "0"(_num) \ - : "memory", "cc" \ - ); \ - _ret; \ -}) - -#define my_syscall5(num, arg1, arg2, arg3, arg4, arg5) \ -({ \ - long _ret; \ - register long _num asm("eax") = (num); \ - register long _arg1 asm("ebx") = (long)(arg1); \ - register long _arg2 asm("ecx") = (long)(arg2); \ - register long _arg3 asm("edx") = (long)(arg3); \ - register long _arg4 asm("esi") = (long)(arg4); \ - register long _arg5 asm("edi") = (long)(arg5); \ - \ - asm volatile ( \ - "int $0x80\n" \ - : "=a" (_ret) \ - : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \ - "0"(_num) \ - : "memory", "cc" \ - ); \ - _ret; \ -}) - -/* startup code */ -/* - * i386 System V ABI mandates: - * 1) last pushed argument must be 16-byte aligned. - * 2) The deepest stack frame should be set to zero - * - */ -asm(".section .text\n" - ".global _start\n" - "_start:\n" - "pop %eax\n" // argc (first arg, %eax) - "mov %esp, %ebx\n" // argv[] (second arg, %ebx) - "lea 4(%ebx,%eax,4),%ecx\n" // then a NULL then envp (third arg, %ecx) - "xor %ebp, %ebp\n" // zero the stack frame - "and $-16, %esp\n" // x86 ABI : esp must be 16-byte aligned before - "sub $4, %esp\n" // the call instruction (args are aligned) - "push %ecx\n" // push all registers on the stack so that we - "push %ebx\n" // support both regparm and plain stack modes - "push %eax\n" - "call main\n" // main() returns the status code in %eax - "mov %eax, %ebx\n" // retrieve exit code (32-bit int) - "movl $1, %eax\n" // NR_exit == 1 - "int $0x80\n" // exit now - "hlt\n" // ensure it does not - ""); - -/* fcntl / open */ -#define O_RDONLY 0 -#define O_WRONLY 1 -#define O_RDWR 2 -#define O_CREAT 0x40 -#define O_EXCL 0x80 -#define O_NOCTTY 0x100 -#define O_TRUNC 0x200 -#define O_APPEND 0x400 -#define O_NONBLOCK 0x800 -#define O_DIRECTORY 0x10000 - -/* The struct returned by the stat() syscall, 32-bit only, the syscall returns - * exactly 56 bytes (stops before the unused array). - */ -struct sys_stat_struct { - unsigned long st_dev; - unsigned long st_ino; - unsigned short st_mode; - unsigned short st_nlink; - unsigned short st_uid; - unsigned short st_gid; - - unsigned long st_rdev; - unsigned long st_size; - unsigned long st_blksize; - unsigned long st_blocks; - - unsigned long st_atime; - unsigned long st_atime_nsec; - unsigned long st_mtime; - unsigned long st_mtime_nsec; - - unsigned long st_ctime; - unsigned long st_ctime_nsec; - unsigned long __unused[2]; -}; - -#elif defined(__ARM_EABI__) -/* Syscalls for ARM in ARM or Thumb modes : - * - registers are 32-bit - * - stack is 8-byte aligned - * ( http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka4127.html) - * - syscall number is passed in r7 - * - arguments are in r0, r1, r2, r3, r4, r5 - * - the system call is performed by calling svc #0 - * - syscall return comes in r0. - * - only lr is clobbered. - * - the arguments are cast to long and assigned into the target registers - * which are then simply passed as registers to the asm code, so that we - * don't have to experience issues with register constraints. - * - the syscall number is always specified last in order to allow to force - * some registers before (gcc refuses a %-register at the last position). - * - * Also, ARM supports the old_select syscall if newselect is not available - */ -#define __ARCH_WANT_SYS_OLD_SELECT - -#define my_syscall0(num) \ -({ \ - register long _num asm("r7") = (num); \ - register long _arg1 asm("r0"); \ - \ - asm volatile ( \ - "svc #0\n" \ - : "=r"(_arg1) \ - : "r"(_num) \ - : "memory", "cc", "lr" \ - ); \ - _arg1; \ -}) - -#define my_syscall1(num, arg1) \ -({ \ - register long _num asm("r7") = (num); \ - register long _arg1 asm("r0") = (long)(arg1); \ - \ - asm volatile ( \ - "svc #0\n" \ - : "=r"(_arg1) \ - : "r"(_arg1), \ - "r"(_num) \ - : "memory", "cc", "lr" \ - ); \ - _arg1; \ -}) - -#define my_syscall2(num, arg1, arg2) \ -({ \ - register long _num asm("r7") = (num); \ - register long _arg1 asm("r0") = (long)(arg1); \ - register long _arg2 asm("r1") = (long)(arg2); \ - \ - asm volatile ( \ - "svc #0\n" \ - : "=r"(_arg1) \ - : "r"(_arg1), "r"(_arg2), \ - "r"(_num) \ - : "memory", "cc", "lr" \ - ); \ - _arg1; \ -}) - -#define my_syscall3(num, arg1, arg2, arg3) \ -({ \ - register long _num asm("r7") = (num); \ - register long _arg1 asm("r0") = (long)(arg1); \ - register long _arg2 asm("r1") = (long)(arg2); \ - register long _arg3 asm("r2") = (long)(arg3); \ - \ - asm volatile ( \ - "svc #0\n" \ - : "=r"(_arg1) \ - : "r"(_arg1), "r"(_arg2), "r"(_arg3), \ - "r"(_num) \ - : "memory", "cc", "lr" \ - ); \ - _arg1; \ -}) - -#define my_syscall4(num, arg1, arg2, arg3, arg4) \ -({ \ - register long _num asm("r7") = (num); \ - register long _arg1 asm("r0") = (long)(arg1); \ - register long _arg2 asm("r1") = (long)(arg2); \ - register long _arg3 asm("r2") = (long)(arg3); \ - register long _arg4 asm("r3") = (long)(arg4); \ - \ - asm volatile ( \ - "svc #0\n" \ - : "=r"(_arg1) \ - : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), \ - "r"(_num) \ - : "memory", "cc", "lr" \ - ); \ - _arg1; \ -}) - -#define my_syscall5(num, arg1, arg2, arg3, arg4, arg5) \ -({ \ - register long _num asm("r7") = (num); \ - register long _arg1 asm("r0") = (long)(arg1); \ - register long _arg2 asm("r1") = (long)(arg2); \ - register long _arg3 asm("r2") = (long)(arg3); \ - register long _arg4 asm("r3") = (long)(arg4); \ - register long _arg5 asm("r4") = (long)(arg5); \ - \ - asm volatile ( \ - "svc #0\n" \ - : "=r" (_arg1) \ - : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \ - "r"(_num) \ - : "memory", "cc", "lr" \ - ); \ - _arg1; \ -}) - -/* startup code */ -asm(".section .text\n" - ".global _start\n" - "_start:\n" -#if defined(__THUMBEB__) || defined(__THUMBEL__) - /* We enter here in 32-bit mode but if some previous functions were in - * 16-bit mode, the assembler cannot know, so we need to tell it we're in - * 32-bit now, then switch to 16-bit (is there a better way to do it than - * adding 1 by hand ?) and tell the asm we're now in 16-bit mode so that - * it generates correct instructions. Note that we do not support thumb1. - */ - ".code 32\n" - "add r0, pc, #1\n" - "bx r0\n" - ".code 16\n" -#endif - "pop {%r0}\n" // argc was in the stack - "mov %r1, %sp\n" // argv = sp - "add %r2, %r1, %r0, lsl #2\n" // envp = argv + 4*argc ... - "add %r2, %r2, $4\n" // ... + 4 - "and %r3, %r1, $-8\n" // AAPCS : sp must be 8-byte aligned in the - "mov %sp, %r3\n" // callee, an bl doesn't push (lr=pc) - "bl main\n" // main() returns the status code, we'll exit with it. - "movs r7, $1\n" // NR_exit == 1 - "svc $0x00\n" - ""); - -/* fcntl / open */ -#define O_RDONLY 0 -#define O_WRONLY 1 -#define O_RDWR 2 -#define O_CREAT 0x40 -#define O_EXCL 0x80 -#define O_NOCTTY 0x100 -#define O_TRUNC 0x200 -#define O_APPEND 0x400 -#define O_NONBLOCK 0x800 -#define O_DIRECTORY 0x4000 - -/* The struct returned by the stat() syscall, 32-bit only, the syscall returns - * exactly 56 bytes (stops before the unused array). In big endian, the format - * differs as devices are returned as short only. - */ -struct sys_stat_struct { -#if defined(__ARMEB__) - unsigned short st_dev; - unsigned short __pad1; -#else - unsigned long st_dev; -#endif - unsigned long st_ino; - unsigned short st_mode; - unsigned short st_nlink; - unsigned short st_uid; - unsigned short st_gid; -#if defined(__ARMEB__) - unsigned short st_rdev; - unsigned short __pad2; -#else - unsigned long st_rdev; -#endif - unsigned long st_size; - unsigned long st_blksize; - unsigned long st_blocks; - unsigned long st_atime; - unsigned long st_atime_nsec; - unsigned long st_mtime; - unsigned long st_mtime_nsec; - unsigned long st_ctime; - unsigned long st_ctime_nsec; - unsigned long __unused[2]; -}; - -#elif defined(__aarch64__) -/* Syscalls for AARCH64 : - * - registers are 64-bit - * - stack is 16-byte aligned - * - syscall number is passed in x8 - * - arguments are in x0, x1, x2, x3, x4, x5 - * - the system call is performed by calling svc 0 - * - syscall return comes in x0. - * - the arguments are cast to long and assigned into the target registers - * which are then simply passed as registers to the asm code, so that we - * don't have to experience issues with register constraints. - * - * On aarch64, select() is not implemented so we have to use pselect6(). - */ -#define __ARCH_WANT_SYS_PSELECT6 - -#define my_syscall0(num) \ -({ \ - register long _num asm("x8") = (num); \ - register long _arg1 asm("x0"); \ - \ - asm volatile ( \ - "svc #0\n" \ - : "=r"(_arg1) \ - : "r"(_num) \ - : "memory", "cc" \ - ); \ - _arg1; \ -}) - -#define my_syscall1(num, arg1) \ -({ \ - register long _num asm("x8") = (num); \ - register long _arg1 asm("x0") = (long)(arg1); \ - \ - asm volatile ( \ - "svc #0\n" \ - : "=r"(_arg1) \ - : "r"(_arg1), \ - "r"(_num) |
