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https://github.com/ptitSeb/box86.git
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Better way to handle syscall array with c99 sparse array init
This commit is contained in:
ptitSeb
parent
949e7b7809
commit
fefa13f655
@ -119,185 +119,184 @@ int my_fcntl(x86emu_t* emu, int fd, int cmd, ... /* arg */ );
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// Syscall table for x86 can be found here: http://shell-storm.org/shellcode/files/syscalls.html
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typedef struct scwrap_s {
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uint32_t x86s;
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int nats;
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int nbpars;
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} scwrap_t;
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scwrap_t syscallwrap[] = {
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{ 2, __NR_fork, 1 }, // should wrap this one, because of the struct pt_regs (the only arg)?
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//{ 3, __NR_read, 3 }, // wrapped so SA_RESTART can be handled by libc
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//{ 4, __NR_write, 3 }, // same
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//{ 5, __NR_open, 3 }, // flags need transformation
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//{ 6, __NR_close, 1 }, // wrapped so SA_RESTART can be handled by libc
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[2] ={ __NR_fork, 1 }, // should wrap this one, because of the struct pt_regs (the only arg)?
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//[3] ={ __NR_read, 3 }, // wrapped so SA_RESTART can be handled by libc
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//[4] ={ __NR_write, 3 }, // same
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//[5] ={ __NR_open, 3 }, // flags need transformation
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//[6] ={ __NR_close, 1 }, // wrapped so SA_RESTART can be handled by libc
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#ifdef __NR_waitpid
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{ 7, __NR_waitpid, 3 },
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[7] ={ __NR_waitpid, 3 },
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#endif
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{ 10, __NR_unlink, 1 },
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{ 12, __NR_chdir, 1 },
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[10] { __NR_unlink, 1 },
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[12] { __NR_chdir, 1 },
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#ifdef __NR_time
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{ 13, __NR_time, 1 },
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[13] { __NR_time, 1 },
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#endif
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{ 15, __NR_chmod, 2 },
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{ 19, __NR_lseek, 3 },
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{ 20, __NR_getpid, 0 },
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{ 24, __NR_getuid, 0 },
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[15] { __NR_chmod, 2 },
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[19] { __NR_lseek, 3 },
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[20] { __NR_getpid, 0 },
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[24] { __NR_getuid, 0 },
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#ifdef __NR_alarm
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{ 27, __NR_alarm, 1 },
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[27] { __NR_alarm, 1 },
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#endif
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{ 33, __NR_access, 2 },
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{ 37, __NR_kill, 2 },
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{ 38, __NR_rename, 2 },
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{ 39, __NR_mkdir, 2 },
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{ 40, __NR_rmdir, 1 },
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{ 41, __NR_dup, 1 },
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{ 42, __NR_pipe, 1 },
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//{ 45, __NR_brk, 1 },
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{ 47, __NR_getgid, 0 },
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{ 49, __NR_geteuid, 0 },
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{ 50, __NR_getegid, 0 },
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{ 54, __NR_ioctl, 3 }, // should be wrapped to allow SA_RESTART handling by libc, but syscall is only 3 arguments, ioctl can be 5
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//{ 55, __NR_fcntl, 3 }, // wrapped to allow filter of F_SETFD
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{ 60, __NR_umask, 1 },
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{ 63, __NR_dup2, 2 },
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{ 64, __NR_getppid, 0 },
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{ 66, __NR_setsid, 0 },
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//{ 67, __NR_sigaction, 3 },
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{ 75, __NR_setrlimit, 2 },
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[33] { __NR_access, 2 },
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[37] { __NR_kill, 2 },
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[38] { __NR_rename, 2 },
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[39] { __NR_mkdir, 2 },
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[40] { __NR_rmdir, 1 },
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[41] { __NR_dup, 1 },
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[42] { __NR_pipe, 1 },
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//[45] { __NR_brk, 1 },
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[47] { __NR_getgid, 0 },
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[49] { __NR_geteuid, 0 },
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[50] { __NR_getegid, 0 },
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[54] { __NR_ioctl, 3 }, // should be wrapped to allow SA_RESTART handling by libc, but syscall is only 3 arguments, ioctl can be 5
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//[55] { __NR_fcntl, 3 }, // wrapped to allow filter of F_SETFD
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[60] { __NR_umask, 1 },
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[63] { __NR_dup2, 2 },
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[64] { __NR_getppid, 0 },
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[66] { __NR_setsid, 0 },
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//[67] { __NR_sigaction, 3 },
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[75] { __NR_setrlimit, 2 },
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#ifdef __NR_getrlimit
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{ 76, __NR_getrlimit, 2 },
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[76] { __NR_getrlimit, 2 },
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#endif
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{ 77, __NR_getrusage, 2 },
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{ 78, __NR_gettimeofday, 2 },
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{ 80, __NR_getgroups, 2 },
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{ 83, __NR_symlink, 2 },
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[77] { __NR_getrusage, 2 },
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[78] { __NR_gettimeofday, 2 },
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[80] { __NR_getgroups, 2 },
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[83] { __NR_symlink, 2 },
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#ifdef __NR_select
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{ 82, __NR_select, 5 },
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[82] { __NR_select, 5 },
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#endif
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{ 85, __NR_readlink, 3 },
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//{ 91, __NR_munmap, 2 },
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{ 94, __NR_fchmod, 2 },
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{ 99, __NR_statfs, 2 },
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[85] { __NR_readlink, 3 },
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//[91] { __NR_munmap, 2 },
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[94] { __NR_fchmod, 2 },
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[99] { __NR_statfs, 2 },
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#ifdef __NR_socketcall
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{ 102, __NR_socketcall, 2 },
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[102] { __NR_socketcall, 2 },
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#endif
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{ 104, __NR_setitimer, 3 },
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{ 105, __NR_getitimer, 2 },
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[104] { __NR_setitimer, 3 },
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[105] { __NR_getitimer, 2 },
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#ifdef __NR_newstat
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{ 106, __NR_newstat, 2 },
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[106] { __NR_newstat, 2 },
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#else
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{ 106, __NR_stat, 2 },
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[106] { __NR_stat, 2 },
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#endif
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#ifdef __NR_newlstat
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{ 107, __NR_newlstat, 2 },
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[107] { __NR_newlstat, 2 },
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#else
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{ 107, __NR_lstat, 2 },
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[107] { __NR_lstat, 2 },
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#endif
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#ifdef __NR_newfstat
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{ 108, __NR_newfstat, 2 },
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[108] { __NR_newfstat, 2 },
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#else
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{ 108, __NR_fstat, 2 },
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[108] { __NR_fstat, 2 },
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#endif
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#ifdef __NR_olduname
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{ 109, __NR_olduname, 1 },
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[109] { __NR_olduname, 1 },
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#endif
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#ifdef __NR_iopl
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{ 110, __NR_iopl, 1 },
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[110] { __NR_iopl, 1 },
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#endif
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{ 114, __NR_wait4, 4 }, //TODO: check struct rusage alignment
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[114] { __NR_wait4, 4 }, //TODO: check struct rusage alignment
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#ifdef __NR_ipc
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{ 117, __NR_ipc, 6 },
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[117] { __NR_ipc, 6 },
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#endif
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//{ 119, __NR_sigreturn, 0},
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//{ 120, __NR_clone, 5 }, // need works
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//{ 122, __NR_uname, 1 },
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//{ 123, __NR_modify_ldt },
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//{ 125, __NR_mprotect, 3 },
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{ 126, __NR_sigprocmask, 3 },
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{ 136, __NR_personality, 1 },
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{ 140, __NR__llseek, 5 },
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{ 141, __NR_getdents, 3 },
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{ 142, __NR__newselect, 5 },
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{ 143, __NR_flock, 2 },
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{ 144, __NR_msync, 3 },
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{ 145, __NR_readv, 3 },
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{ 146, __NR_writev, 3 },
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{ 148, __NR_fdatasync, 1 },
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{ 149, __NR__sysctl, 1 }, // need wrapping?
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{ 156, __NR_sched_setscheduler, 3 },
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{ 157, __NR_sched_getscheduler, 1 },
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{ 158, __NR_sched_yield, 0 },
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{ 162, __NR_nanosleep, 2 },
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{ 164, __NR_setresuid, 3 },
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//{ 168, __NR_poll, 3 }, // wrapped to allow SA_RESTART wrapping by libc
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{ 172, __NR_prctl, 5 },
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//{ 173, __NR_rt_sigreturn, 0 },
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{ 175, __NR_rt_sigprocmask, 4 },
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{ 179, __NR_rt_sigsuspend, 2 },
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{ 183, __NR_getcwd, 2 },
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{ 184, __NR_capget, 2},
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{ 185, __NR_capset, 2},
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{ 186, __NR_sigaltstack, 2 }, // neeed wrap or something?
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{ 191, __NR_ugetrlimit, 2 },
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// { 192, __NR_mmap2, 6},
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//{ 195, __NR_stat64, 2 }, // need proprer wrap because of structure size change
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//{ 196, __NR_lstat64, 2 }, // need proprer wrap because of structure size change
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//{ 197, __NR_fstat64, 2 }, // need proprer wrap because of structure size change
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//[119] { __NR_sigreturn, 0},
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//[120] { __NR_clone, 5 }, // need works
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//[122] { __NR_uname, 1 },
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//[123] { __NR_modify_ldt },
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//[125] { __NR_mprotect, 3 },
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[126] { __NR_sigprocmask, 3 },
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[136] { __NR_personality, 1 },
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[140] { __NR__llseek, 5 },
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[141] { __NR_getdents, 3 },
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[142] { __NR__newselect, 5 },
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[143] { __NR_flock, 2 },
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[144] { __NR_msync, 3 },
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[145] { __NR_readv, 3 },
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[146] { __NR_writev, 3 },
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[148] { __NR_fdatasync, 1 },
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[149] { __NR__sysctl, 1 }, // need wrapping?
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[156] { __NR_sched_setscheduler, 3 },
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[157] { __NR_sched_getscheduler, 1 },
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[158] { __NR_sched_yield, 0 },
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[162] { __NR_nanosleep, 2 },
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[164] { __NR_setresuid, 3 },
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//[168] { __NR_poll, 3 }, // wrapped to allow SA_RESTART wrapping by libc
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[172] { __NR_prctl, 5 },
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//[173] { __NR_rt_sigreturn, 0 },
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[175] { __NR_rt_sigprocmask, 4 },
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[179] { __NR_rt_sigsuspend, 2 },
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[183] { __NR_getcwd, 2 },
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[184] { __NR_capget, 2},
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[185] { __NR_capset, 2},
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[186] { __NR_sigaltstack, 2 }, // neeed wrap or something?
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[191] { __NR_ugetrlimit, 2 },
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// [192] { __NR_mmap2, 6},
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//[195] { __NR_stat64, 2 }, // need proprer wrap because of structure size change
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//[196] { __NR_lstat64, 2 }, // need proprer wrap because of structure size change
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//[197] { __NR_fstat64, 2 }, // need proprer wrap because of structure size change
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#ifndef POWERPCLE
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{ 199, __NR_getuid32, 0 },
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{ 200, __NR_getgid32, 0 },
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{ 201, __NR_geteuid32, 0 },
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{ 202, __NR_getegid32, 0 },
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{ 208, __NR_setresuid32, 3 },
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{ 209, __NR_getresuid32, 3 },
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{ 210, __NR_setresgid32, 3 },
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{ 211, __NR_getresgid32, 3 },
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[199] { __NR_getuid32, 0 },
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[200] { __NR_getgid32, 0 },
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[201] { __NR_geteuid32, 0 },
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[202] { __NR_getegid32, 0 },
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[208] { __NR_setresuid32, 3 },
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[209] { __NR_getresuid32, 3 },
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[210] { __NR_setresgid32, 3 },
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[211] { __NR_getresgid32, 3 },
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#else
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// PowerPC uses the same syscalls for 32/64 bit processes.
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{ 199, __NR_getuid, 0 },
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{ 200, __NR_getgid, 0 },
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{ 201, __NR_geteuid, 0 },
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{ 202, __NR_getegid, 0 },
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{ 208, __NR_setresuid, 3 },
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{ 209, __NR_getresuid, 3 },
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{ 210, __NR_setresgid, 3 },
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{ 211, __NR_getresgid, 3 },
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[199] { __NR_getuid, 0 },
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[200] { __NR_getgid, 0 },
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[201] { __NR_geteuid, 0 },
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[202] { __NR_getegid, 0 },
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[208] { __NR_setresuid, 3 },
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[209] { __NR_getresuid, 3 },
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[210] { __NR_setresgid, 3 },
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[211] { __NR_getresgid, 3 },
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#endif
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{ 220, __NR_getdents64, 3 },
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//{ 221, __NR_fcntl64, 3 },
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{ 224, __NR_gettid, 0 },
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{ 240, __NR_futex, 6 },
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{ 241, __NR_sched_setaffinity, 3 },
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{ 242, __NR_sched_getaffinity, 3 },
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{ 252, __NR_exit_group, 1 },
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[220] { __NR_getdents64, 3 },
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//[221] { __NR_fcntl64, 3 },
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[224] { __NR_gettid, 0 },
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[240] { __NR_futex, 6 },
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[241] { __NR_sched_setaffinity, 3 },
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[242] { __NR_sched_getaffinity, 3 },
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[252] { __NR_exit_group, 1 },
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#ifdef NOALIGN
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{ 254, __NR_epoll_create, 1 },
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{ 255, __NR_epoll_ctl, 4 },
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{ 256, __NR_epoll_wait, 4 },
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[254] { __NR_epoll_create, 1 },
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[255] { __NR_epoll_ctl, 4 },
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[256] { __NR_epoll_wait, 4 },
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#endif
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{ 265, __NR_clock_gettime, 2 },
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{ 266, __NR_clock_getres, 2 },
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//{ 270, __NR_tgkill, 3 },
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{ 271, __NR_utimes, 2 },
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{ 291, __NR_inotify_init, 0},
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{ 292, __NR_inotify_add_watch, 3},
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{ 293, __NR_inotify_rm_watch, 2},
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{ 311, __NR_set_robust_list, 2 },
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{ 312, __NR_get_robust_list, 4 },
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{ 318, __NR_getcpu, 3},
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{ 328, __NR_eventfd2, 2},
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[265] { __NR_clock_gettime, 2 },
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[266] { __NR_clock_getres, 2 },
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//[270] { __NR_tgkill, 3 },
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[271] { __NR_utimes, 2 },
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[291] { __NR_inotify_init, 0},
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[292] { __NR_inotify_add_watch, 3},
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[293] { __NR_inotify_rm_watch, 2},
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[311] { __NR_set_robust_list, 2 },
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[312] { __NR_get_robust_list, 4 },
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[318] { __NR_getcpu, 3},
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[328] { __NR_eventfd2, 2},
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#ifdef NOALIGN
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{ 329, __NR_epoll_create1, 1 },
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[329] { __NR_epoll_create1, 1 },
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#endif
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{ 331, __NR_pipe2, 2},
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{ 332, __NR_inotify_init1, 1},
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[331] { __NR_pipe2, 2},
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[332] { __NR_inotify_init1, 1},
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#ifdef __NR_getrandom
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{ 355, __NR_getrandom, 3 },
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[355] { __NR_getrandom, 3 },
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#endif
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#ifdef __NR_memfd_create
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{ 356, __NR_memfd_create, 2},
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[356] { __NR_memfd_create, 2},
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#endif
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//{ 449, __NR_futex_waitv, 5},
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//[449] { __NR_futex_waitv, 5},
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};
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struct mmap_arg_struct {
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@ -412,27 +411,25 @@ void EXPORT x86Syscall(x86emu_t *emu)
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printf_log(LOG_DEBUG, "%p: Calling syscall 0x%02X (%d) %p %p %p %p %p", (void*)R_EIP, s, s, (void*)R_EBX, (void*)R_ECX, (void*)R_EDX, (void*)R_ESI, (void*)R_EDI);
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// check wrapper first
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int cnt = sizeof(syscallwrap) / sizeof(scwrap_t);
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for (int i=0; i<cnt; i++) {
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if(syscallwrap[i].x86s == s) {
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int sc = syscallwrap[i].nats;
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switch(syscallwrap[i].nbpars) {
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case 0: S_EAX = syscall(sc); break;
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case 1: S_EAX = syscall(sc, R_EBX); break;
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case 2: if(s==33) {printf_log(LOG_DEBUG, " => sys_access(\"%s\", %d)\n", (char*)R_EBX, R_ECX);}; S_EAX = syscall(sc, R_EBX, R_ECX); break;
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case 3: S_EAX = syscall(sc, R_EBX, R_ECX, R_EDX); break;
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case 4: S_EAX = syscall(sc, R_EBX, R_ECX, R_EDX, R_ESI); break;
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case 5: S_EAX = syscall(sc, R_EBX, R_ECX, R_EDX, R_ESI, R_EDI); break;
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case 6: S_EAX = syscall(sc, R_EBX, R_ECX, R_EDX, R_ESI, R_EDI, R_EBP); break;
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default:
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printf_log(LOG_NONE, "ERROR, Unimplemented syscall wrapper (%d, %d)\n", s, syscallwrap[i].nbpars);
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emu->quit = 1;
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return;
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}
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if(S_EAX==-1 && errno>0)
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S_EAX = -errno;
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printf_log(LOG_DEBUG, " => 0x%x\n", R_EAX);
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return;
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if(s<cnt && syscallwrap[s].nats) {
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int sc = syscallwrap[s].nats;
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switch(syscallwrap[s].nbpars) {
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case 0: S_EAX = syscall(sc); break;
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case 1: S_EAX = syscall(sc, R_EBX); break;
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case 2: if(s==33) {printf_log(LOG_DEBUG, " => sys_access(\"%s\", %d)\n", (char*)R_EBX, R_ECX);}; S_EAX = syscall(sc, R_EBX, R_ECX); break;
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case 3: S_EAX = syscall(sc, R_EBX, R_ECX, R_EDX); break;
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case 4: S_EAX = syscall(sc, R_EBX, R_ECX, R_EDX, R_ESI); break;
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case 5: S_EAX = syscall(sc, R_EBX, R_ECX, R_EDX, R_ESI, R_EDI); break;
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case 6: S_EAX = syscall(sc, R_EBX, R_ECX, R_EDX, R_ESI, R_EDI, R_EBP); break;
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default:
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printf_log(LOG_NONE, "ERROR, Unimplemented syscall wrapper (%d, %d)\n", s, syscallwrap[s].nbpars);
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emu->quit = 1;
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return;
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}
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if(S_EAX==-1 && errno>0)
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S_EAX = -errno;
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printf_log(LOG_DEBUG, " => 0x%x\n", R_EAX);
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return;
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}
|
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switch (s) {
|
||||
case 1: // sys_exit
|
||||
@ -798,22 +795,20 @@ long EXPORT my_syscall(x86emu_t *emu)
|
||||
printf_log(LOG_DEBUG, "%p: Calling libc syscall 0x%02X (%d) %p %p %p %p %p\n", (void*)R_EIP, s, s, (void*)u32(4), (void*)u32(8), (void*)u32(12), (void*)u32(16), (void*)u32(20));
|
||||
// check wrapper first
|
||||
int cnt = sizeof(syscallwrap) / sizeof(scwrap_t);
|
||||
for (int i=0; i<cnt; i++) {
|
||||
if(syscallwrap[i].x86s == s) {
|
||||
int sc = syscallwrap[i].nats;
|
||||
switch(syscallwrap[i].nbpars) {
|
||||
case 0: return syscall(sc);
|
||||
case 1: return syscall(sc, u32(4));
|
||||
case 2: return syscall(sc, u32(4), u32(8));
|
||||
case 3: return syscall(sc, u32(4), u32(8), u32(12));
|
||||
case 4: return syscall(sc, u32(4), u32(8), u32(12), u32(16));
|
||||
case 5: return syscall(sc, u32(4), u32(8), u32(12), u32(16), u32(20));
|
||||
case 6: return syscall(sc, u32(4), u32(8), u32(12), u32(16), u32(20), u32(24));
|
||||
default:
|
||||
printf_log(LOG_NONE, "ERROR, Unimplemented syscall wrapper (%d, %d)\n", s, syscallwrap[i].nbpars);
|
||||
emu->quit = 1;
|
||||
return 0;
|
||||
}
|
||||
if(s<cnt && syscallwrap[s].nats) {
|
||||
int sc = syscallwrap[s].nats;
|
||||
switch(syscallwrap[s].nbpars) {
|
||||
case 0: return syscall(sc);
|
||||
case 1: return syscall(sc, u32(4));
|
||||
case 2: return syscall(sc, u32(4), u32(8));
|
||||
case 3: return syscall(sc, u32(4), u32(8), u32(12));
|
||||
case 4: return syscall(sc, u32(4), u32(8), u32(12), u32(16));
|
||||
case 5: return syscall(sc, u32(4), u32(8), u32(12), u32(16), u32(20));
|
||||
case 6: return syscall(sc, u32(4), u32(8), u32(12), u32(16), u32(20), u32(24));
|
||||
default:
|
||||
printf_log(LOG_NONE, "ERROR, Unimplemented syscall wrapper (%d, %d)\n", s, syscallwrap[s].nbpars);
|
||||
emu->quit = 1;
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
switch (s) {
|
||||
|
||||
Loading…
Reference in New Issue
Block a user