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#if HAVE_CONFIG_H
#include "config.h"
#endif
#define _GNU_SOURCE 1
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <signal.h>
#include <string.h>
#include "ltrace.h"
#include "options.h"
#include "debug.h"
static struct event event;
/* This should also update `current_process' */
static struct process *pid2proc(int pid);
struct event *wait_for_something(void)
{
pid_t pid;
int status;
int tmp;
int stop_signal;
if (!list_of_processes) {
debug(1, "No more children");
exit(0);
}
pid = wait(&status);
if (pid == -1) {
if (errno == ECHILD) {
debug(1, "No more children");
exit(0);
} else if (errno == EINTR) {
debug(1, "wait received EINTR ?");
event.thing = LT_EV_NONE;
return &event;
}
perror("wait");
exit(1);
}
event.proc = pid2proc(pid);
if (!event.proc) {
fprintf(stderr, "signal from wrong pid %u ?!?\n", pid);
exit(1);
}
get_arch_dep(event.proc);
event.proc->instruction_pointer = NULL;
debug(3, "signal from pid %u", pid);
if (event.proc->breakpoints_enabled == -1) {
enable_all_breakpoints(event.proc);
event.thing = LT_EV_NONE;
trace_set_options(event.proc, event.proc->pid);
continue_process(event.proc->pid);
return &event;
}
if (opt_i) {
event.proc->instruction_pointer =
get_instruction_pointer(event.proc);
}
switch (syscall_p(event.proc, status, &tmp)) {
case 1:
event.thing = LT_EV_SYSCALL;
event.e_un.sysnum = tmp;
return &event;
case 2:
event.thing = LT_EV_SYSRET;
event.e_un.sysnum = tmp;
return &event;
case 3:
event.thing = LT_EV_ARCH_SYSCALL;
event.e_un.sysnum = tmp;
return &event;
case 4:
event.thing = LT_EV_ARCH_SYSRET;
event.e_un.sysnum = tmp;
return &event;
case -1:
event.thing = LT_EV_NONE;
continue_process(event.proc->pid);
return &event;
}
if (WIFEXITED(status)) {
event.thing = LT_EV_EXIT;
event.e_un.ret_val = WEXITSTATUS(status);
return &event;
}
if (WIFSIGNALED(status)) {
event.thing = LT_EV_EXIT_SIGNAL;
event.e_un.signum = WTERMSIG(status);
return &event;
}
if (!WIFSTOPPED(status)) {
event.thing = LT_EV_UNKNOWN;
return &event;
}
stop_signal = WSTOPSIG(status);
/* On some targets, breakpoints are signalled not using
SIGTRAP, but also with SIGILL, SIGSEGV or SIGEMT. Check
for these. */
if (stop_signal == SIGSEGV
|| stop_signal == SIGILL
#ifdef SIGEMT
|| stop_signal == SIGEMT
#endif
) {
// If we didn't need to know IP so far, get it now.
void * addr = opt_i
? event.proc->instruction_pointer
: (event.proc->instruction_pointer = get_instruction_pointer (event.proc));
if (address2bpstruct(event.proc, addr))
stop_signal = SIGTRAP;
}
if (stop_signal != (SIGTRAP | event.proc->tracesysgood)
&& stop_signal != SIGTRAP) {
event.thing = LT_EV_SIGNAL;
event.e_un.signum = stop_signal;
return &event;
}
if (was_exec(event.proc, status)) {
pid_t saved_pid;
event.thing = LT_EV_NONE;
event.e_un.signum = WSTOPSIG(status);
debug(1, "Placing breakpoints for the new program");
event.proc->mask_32bit = 0;
event.proc->personality = 0;
event.proc->arch_ptr = NULL;
event.proc->filename = pid2name(event.proc->pid);
saved_pid = event.proc->pid;
event.proc->pid = 0;
breakpoints_init(event.proc);
event.proc->pid = saved_pid;
continue_process(event.proc->pid);
return &event;
}
event.thing = LT_EV_BREAKPOINT;
if (!event.proc->instruction_pointer) {
event.proc->instruction_pointer =
get_instruction_pointer(event.proc);
}
event.e_un.brk_addr =
event.proc->instruction_pointer - DECR_PC_AFTER_BREAK;
return &event;
}
static struct process *pid2proc(pid_t pid)
{
struct process *tmp;
tmp = list_of_processes;
while (tmp) {
if (pid == tmp->pid) {
return tmp;
}
tmp = tmp->next;
}
return NULL;
}
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