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debugger: Add support for FreeBSD
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@dd86k
dd86k committed Sep 3, 2024
1 parent 07db444 commit d74c673
Showing 1 changed file with 113 additions and 35 deletions.
148 changes: 113 additions & 35 deletions src/adbg/debugger.d
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Original file line number Diff line number Diff line change
Expand Up @@ -32,8 +32,9 @@ version (Windows) {
import adbg.platform : ADBG_CHILD_STACK_SIZE;
}

//version (CRuntime_Glibc)
// version = USE_CLONE;
version (linux)
//version (CRuntime_Glibc)
enum USE_CLONE = false;

extern (C):

Expand Down Expand Up @@ -245,6 +246,10 @@ version (Windows) {
return null;
}
}

proc.status = AdbgProcStatus.standby;
proc.creation = AdbgCreation.spawned;
return proc;
} else version (linux) {
// NOTE: Don't remember this check, but I think it was because of
// an ambiguous error message
Expand Down Expand Up @@ -272,7 +277,7 @@ version (Windows) {
memcpy(proc.argv + 1, argv, argc * size_t.sizeof);
proc.argv[argc + 1] = null;

version (USE_CLONE) { // clone(2)
static if (USE_CLONE) { // clone(2)
//TODO: get default stack size (glibc constant or function)
void *stack = mmap(null, ADBG_CHILD_STACK_SIZE,
PROT_READ | PROT_WRITE,
Expand Down Expand Up @@ -320,11 +325,63 @@ version (USE_CLONE) { // clone(2)
default: // This parent process
} // switch(fork(2))
} // clone(2)/fork(2)
} // version (linux)

proc.status = AdbgProcStatus.standby;
proc.creation = AdbgCreation.spawned;
return proc;
} else version (FreeBSD) {
// Verify if file exists and we has access to it
stat_t st = void;
if (stat(path, &st) == -1) {
adbg_process_free(proc);
adbg_oops(AdbgError.os);
return null;
}

// Allocate arguments, include space for program and null terminator
int argc;
while (argv[argc]) ++argc;
version(Trace) trace("argc=%d", argc);
proc.argv = cast(char**)malloc((argc + 2) * size_t.sizeof);
if (proc.argv == null) {
version(Trace) trace("mmap=%s", strerror(errno));
adbg_process_free(proc);
adbg_oops(AdbgError.os);
return null;
}
proc.argv[0] = cast(char*)path;
if (argc && argv && *argv)
memcpy(proc.argv + 1, argv, argc * size_t.sizeof);
proc.argv[argc + 1] = null;

switch (proc.pid = fork()) {
case -1: // Error
version(Trace) trace("fork=%s", strerror(errno));
adbg_process_free(proc);
adbg_oops(AdbgError.os);
return null;
case 0: // New child process
version(Trace) for (int i; i < argc + 2; ++i)
trace("argv[%d]=%s", i, proc.argv[i]);

__adbg_child_t chld = void;
chld.argv = cast(const(char)**)proc.argv;
chld.envp = envp;
chld.dir = dir;
__adbg_exec_child(&chld); // If returns at all, error
adbg_process_free(proc);
_exit(errno);
return null; // Make compiler happy
default: // This parent process
} // switch(fork(2))

proc.status = AdbgProcStatus.standby;
proc.creation = AdbgCreation.spawned;
return proc;
} else {
adbg_oops(AdbgError.unimplemented);
return null;
}
}

version (Posix)
Expand Down Expand Up @@ -440,71 +497,70 @@ version (Windows) {
FALSE,
cast(DWORD)pid);
if (proc.hpid == null) {
free(proc);
adbg_oops(AdbgError.os);
free(proc);
return null;
}

// Check if process already has an attached debugger
BOOL dbgpresent = void;
if (CheckRemoteDebuggerPresent(proc.hpid, &dbgpresent) == FALSE) {
adbg_process_free(proc);
adbg_oops(AdbgError.os);
adbg_process_free(proc);
return null;
}
if (dbgpresent) {
adbg_process_free(proc);
adbg_oops(AdbgError.debuggerPresent);
adbg_process_free(proc);
return null;
}

// Breaks into remote process and initiates break-in
//TODO: try NtContinue for continue option
if (DebugActiveProcess(proc.pid) == FALSE) {
adbg_process_free(proc);
adbg_oops(AdbgError.os);
adbg_process_free(proc);
return null;
}

// DebugActiveProcess, by default, kills the process on exit.
// Set exitkill unconditionalled
// Default: on
if (DebugSetProcessKillOnExit(options & OPT_EXITKILL) == FALSE) {
adbg_process_free(proc);
adbg_oops(AdbgError.os);
adbg_process_free(proc);
return null;
}
} else version (Posix) {
} else version (linux) {
version (Trace) if (options & OPT_STOP) trace("Sending break...");
version (linux) {
if (ptrace(options & OPT_STOP ? PT_ATTACH : PT_SEIZE, pid, null, null) < 0) {
adbg_process_free(proc);
adbg_oops(AdbgError.os);
adbg_process_free(proc);
return null;
}

// Set exitkill on if specified
// Default: off
if (options & OPT_EXITKILL && ptrace(PT_SETOPTIONS, pid, null, PT_O_EXITKILL) < 0) {
adbg_process_free(proc);
adbg_oops(AdbgError.os);
adbg_process_free(proc);
return null;
}

proc.status = options & OPT_STOP ? AdbgProcStatus.paused : AdbgProcStatus.running;
} else {
proc.pid = cast(pid_t)pid;
} else version (Posix) {
version (Trace) if (options & OPT_STOP) trace("Sending break...");
if (ptrace(PT_ATTACH, pid, null, 0) < 0) {
adbg_process_free(proc);
adbg_oops(AdbgError.os);
adbg_process_free(proc);
return null;
}

// TODO: Check if running under FreeBSD
// TODO: Check if paused under FreeBSD
proc.status = AdbgProcStatus.running;
}

proc.pid = cast(pid_t)pid;
} // version (Posix)
}

proc.creation = AdbgCreation.attached;
return proc;
Expand Down Expand Up @@ -571,7 +627,7 @@ int adbg_debugger_wait(adbg_process_t *tracee,

version (Windows) {
DEBUG_EVENT de = void;
L_DEBUG_LOOP:
Lwait:
// Something bad happened
if (WaitForDebugEvent(&de, INFINITE) == FALSE) {
tracee.status = AdbgProcStatus.unloaded;
Expand All @@ -592,10 +648,10 @@ L_DEBUG_LOOP:
case RIP_EVENT:
goto default;*/
case EXIT_PROCESS_DEBUG_EVENT:
goto L_UNLOADED;
goto Lexited;
default:
ContinueDebugEvent(de.dwProcessId, de.dwThreadId, DBG_CONTINUE);
goto L_DEBUG_LOOP;
goto Lwait;
}

// Fixes access to debugger, thread context functions.
Expand All @@ -607,10 +663,10 @@ L_DEBUG_LOOP:
FALSE, de.dwThreadId);
tracee.status = AdbgProcStatus.paused;
adbg_exception_translate(&exception, &de, null);
} else version (Posix) {
} else version (linux) {
int wstatus = void;
int stopsig = void;
L_DEBUG_LOOP:
Lwait:
tracee.pid = waitpid(-1, &wstatus, 0);

version (Trace) trace("wstatus=%#x", wstatus);
Expand All @@ -624,14 +680,13 @@ L_DEBUG_LOOP:

// If exited or killed by signal, it's gone.
if (WIFEXITED(wstatus) || WIFSIGNALED(wstatus))
goto L_UNLOADED;
goto Lexited;

// Skip glibc "continue" signals.
version (CRuntime_Glibc)
if (WIFCONTINUED(wstatus))
goto L_DEBUG_LOOP;
goto Lwait;

//TODO: Check waitpid status for BSDs
// Bits Description (Linux)
// 6:0 Signo that caused child to exit
// 0x7f if child stopped/continued
Expand All @@ -642,9 +697,8 @@ L_DEBUG_LOOP:
stopsig = WEXITSTATUS(wstatus);

// Get fault address
version (linux) {
switch (stopsig) {
case SIGCONT: goto L_DEBUG_LOOP;
case SIGCONT: goto Lwait;
// NOTE: si_addr is NOT populated under ptrace for SIGTRAP
// - linux does not fill si_addr on a SIGTRAP from a ptrace event
// - see sigaction(2)
Expand Down Expand Up @@ -677,18 +731,40 @@ version (linux) {
default:
exception.fault_address = 0;
}
} else {
exception.fault_address = 0;
}

tracee.status = AdbgProcStatus.paused;
adbg_exception_translate(&exception, &tracee.pid, &stopsig);
} else version (Posix) {
int wstatus = void;
int stopsig = void;
Lwait:
tracee.pid = waitpid(-1, &wstatus, 0);

version (Trace) trace("wstatus=%#x", wstatus);

// Something bad happened
if (tracee.pid < 0) {
tracee.status = AdbgProcStatus.unloaded;
tracee.creation = AdbgCreation.unloaded;
return adbg_oops(AdbgError.crt);
}

// If exited or killed by signal, it's gone.
if (WIFEXITED(wstatus) || WIFSIGNALED(wstatus))
goto Lexited;

//TODO: Check waitpid status for BSDs
stopsig = WEXITSTATUS(wstatus);

exception.fault_address = 0;
tracee.status = AdbgProcStatus.paused;
adbg_exception_translate(&exception, &tracee.pid, &stopsig);
}

userfunc(tracee, AdbgEvent.exception, &exception);
return 0;

L_UNLOADED:
Lexited:
tracee.status = AdbgProcStatus.unloaded;
tracee.creation = AdbgCreation.unloaded;
return 0;
Expand All @@ -702,6 +778,8 @@ int adbg_debugger_terminate(adbg_process_t *tracee) {
return adbg_oops(AdbgError.invalidArgument);
if (tracee.creation == AdbgCreation.unloaded)
return adbg_oops(AdbgError.debuggerUnattached);
if (tracee.pid == 0)
return adbg_oops(AdbgError.debuggerUnattached);

tracee.status = AdbgProcStatus.unloaded; // exited in any case
tracee.creation = AdbgCreation.unloaded;
Expand All @@ -715,7 +793,7 @@ version (Windows) {
if (ContinueDebugEvent(tracee.pid, tracee.tid, DBG_TERMINATE_PROCESS) == FALSE)
return adbg_oops(AdbgError.os);
} else {
if (kill(tracee.pid, SIGKILL) < 0) // PT_KILL is deprecated
if (kill(tracee.pid, SIGKILL) < 0) // PT_KILL is deprecated on Linux
return adbg_oops(AdbgError.os);
}

Expand Down Expand Up @@ -797,7 +875,7 @@ version (Windows) {

return 0;
} else {
if (ptrace(PT_SINGLESTEP, tracee.pid, null, 0) < 0) {
if (ptrace(PT_STEP, tracee.pid, null, 0) < 0) {
tracee.status = AdbgProcStatus.unknown;
return adbg_oops(AdbgError.os);
}
Expand Down

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