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libc: Propagate all errors in execl() and execvpe() + add execle().
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apio 2023-04-25 17:42:19 +02:00
parent b8ca749a6c
commit 89fd57dea4
Signed by: apio
GPG Key ID: B8A7D06E42258954
2 changed files with 97 additions and 52 deletions
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3
libc/include/unistd.h
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@ -64,6 +64,9 @@ extern "C"
/* Replace the current process with another one. On success, does not return. */
int execl(const char* path, const char* arg, ...);
/* Replace the current process with another one. On success, does not return. */
int execle(const char* path, const char* arg, ...);
/* Replace the current process with another one. On success, does not return. */
int execve(const char* path, char* const* argv, char* const* envp);

144
libc/src/unistd.cpp
View File

@ -15,6 +15,71 @@ extern "C" long arch_invoke_syscall(long, uintptr_t, uintptr_t, uintptr_t, uintp
extern char** environ;
static Result<int> try_execvpe(const char* name, char* const* argv, char* const* envp)
{
if (strchr(name, '/')) return execve(name, argv, envp);
char* path = getenv("PATH");
if (!path) path = const_cast<char*>("/bin:/sbin");
Vector<String> paths = TRY(StringView { path }.split(":"));
for (const auto& dir : paths)
{
StringBuilder sb;
TRY(sb.add(dir));
TRY(sb.add('/'));
TRY(sb.add(StringView { name }));
String file = TRY(sb.string());
int err = errno;
execve(file.chars(), argv, envp);
if (errno != ENOENT && errno != EACCES && errno != ENOEXEC) return -1;
if (errno == ENOEXEC)
{
Vector<char*> shell_argv;
TRY(shell_argv.try_append(const_cast<char*>("sh")));
char* const* arg = argv;
do {
TRY(shell_argv.try_append(*arg));
} while (*(arg++));
execve("/bin/sh", shell_argv.data(), envp);
errno = ENOEXEC;
return -1;
}
if (err == EACCES) errno = err;
}
return -1;
}
static Result<int> try_execl(const char* path, const char* arg, bool use_environ, va_list ap)
{
Vector<char*> args;
TRY(args.try_append(const_cast<char*>(arg)));
while (true)
{
char* str = va_arg(ap, char*);
TRY(args.try_append(str));
if (!str) break;
}
if (use_environ)
{
char* const* envp = va_arg(ap, char* const*);
return execve(path, args.data(), envp);
}
return execv(path, args.data());
}
extern "C"
{
pid_t fork(void)
@ -102,50 +167,13 @@ extern "C"
int execvpe(const char* name, char* const* argv, char* const* envp)
{
if (strchr(name, '/')) return execve(name, argv, envp);
char* path = getenv("PATH");
if (!path) path = const_cast<char*>("/bin:/sbin");
Vector<String> paths;
bool ok = StringView { path }.split(":").try_move_value_or_error(paths, errno);
if (!ok) return -1;
for (const auto& dir : paths)
auto rc = try_execvpe(name, argv, envp);
if (rc.has_error())
{
// FIXME: Check for errors.
StringBuilder sb;
sb.add(dir);
sb.add('/');
sb.add(StringView { name });
String file;
ok = sb.string().try_move_value_or_error(file, errno);
if (!ok) return -1;
int err = errno;
execve(file.chars(), argv, envp);
if (errno != ENOENT && errno != EACCES && errno != ENOEXEC) return -1;
if (errno == ENOEXEC)
{
Vector<char*> shell_argv;
shell_argv.try_append(const_cast<char*>("sh"));
char* const* arg = argv;
do {
shell_argv.try_append(*arg);
} while (*(arg++));
execve("/bin/sh", shell_argv.data(), envp);
errno = ENOEXEC;
errno = rc.error();
return -1;
}
if (err == EACCES) errno = err;
}
return -1;
return rc.value();
}
int execvp(const char* name, char* const* argv)
@ -158,19 +186,33 @@ extern "C"
va_list ap;
va_start(ap, arg);
Vector<char*> args;
if (args.try_append(const_cast<char*>(arg)).has_error()) return -1;
while (true)
{
char* str = va_arg(ap, char*);
if (args.try_append(str).has_error()) return -1;
if (!str) break;
}
auto rc = try_execl(path, arg, false, ap);
va_end(ap);
return execv(path, args.data());
if (rc.has_error())
{
errno = rc.error();
return -1;
}
return rc.value();
}
int execle(const char* path, const char* arg, ...)
{
va_list ap;
va_start(ap, arg);
auto rc = try_execl(path, arg, true, ap);
va_end(ap);
if (rc.has_error())
{
errno = rc.error();
return -1;
}
return rc.value();
}
long syscall(long num, ...)