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/*
* SPDX-FileCopyrightText: 2009 , Nicolas François
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <config.h>
#ident "$Id$"
#include "prototypes.h"
#include "defines.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "string/sprintf.h"
int
get_pid(const char *pidstr, pid_t *pid)
{
char *end;
long long val;
errno = 0;
val = strtoll(pidstr, &end, 10);
if ( ('\0' == *pidstr)
|| ('\0' != *end)
|| (0 != errno)
|| (val < 1)
|| (/*@+longintegral@*/val != (pid_t)val)/*@=longintegral@*/) {
return -1;
}
*pid = val;
return 0;
}
/*
* If use passed in fd:4 as an argument, then return the
* value '4', the fd to use.
* On error, return -1.
*/
int get_pidfd_from_fd(const char *pidfdstr)
{
char *end;
long long val;
struct stat st;
dev_t proc_st_dev, proc_st_rdev;
errno = 0;
val = strtoll(pidfdstr, &end, 10);
if ( ('\0' == *pidfdstr)
|| ('\0' != *end)
|| (0 != errno)
|| (val < 0)
|| (/*@+longintegral@*/val != (int)val)/*@=longintegral@*/) {
return -1;
}
if (stat("/proc/self/uid_map", &st) < 0) {
return -1;
}
proc_st_dev = st.st_dev;
proc_st_rdev = st.st_rdev;
if (fstat(val, &st) < 0) {
return -1;
}
if (st.st_dev != proc_st_dev || st.st_rdev != proc_st_rdev) {
return -1;
}
return (int)val;
}
int open_pidfd(const char *pidstr)
{
int proc_dir_fd;
char proc_dir_name[32];
pid_t target;
if (get_pid(pidstr, &target) == -1)
return -ENOENT;
/* max string length is 6 + 10 + 1 + 1 = 18, allocate 32 bytes */
if (SNPRINTF(proc_dir_name, "/proc/%u/", target) == -1) {
fprintf(stderr, "snprintf of proc path failed for %u: %s\n",
target, strerror(errno));
return -EINVAL;
}
proc_dir_fd = open(proc_dir_name, O_DIRECTORY);
if (proc_dir_fd < 0) {
fprintf(stderr, _("Could not open proc directory for target %u: %s\n"),
target, strerror(errno));
return -EINVAL;
}
return proc_dir_fd;
}
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