Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0
#include <linux/compiler.h>
#include <linux/string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include "subcmd-util.h"
#include "exec-cmd.h"
#include "subcmd-config.h"
 
#define MAX_ARGS	32
#define PATH_MAX	4096
 
static const char *argv_exec_path;
static const char *argv0_path;
 
void exec_cmd_init(const char *exec_name, const char *prefix,
<------><------>   const char *exec_path, const char *exec_path_env)
{
<------>subcmd_config.exec_name		= exec_name;
<------>subcmd_config.prefix		= prefix;
<------>subcmd_config.exec_path		= exec_path;
<------>subcmd_config.exec_path_env	= exec_path_env;
}
 
#define is_dir_sep(c) ((c) == '/')
 
static int is_absolute_path(const char *path)
{
<------>return path[0] == '/';
}
 
static const char *get_pwd_cwd(void)
{
<------>static char cwd[PATH_MAX + 1];
<------>char *pwd;
<------>struct stat cwd_stat, pwd_stat;
<------>if (getcwd(cwd, PATH_MAX) == NULL)
<------><------>return NULL;
<------>pwd = getenv("PWD");
<------>if (pwd && strcmp(pwd, cwd)) {
<------><------>stat(cwd, &cwd_stat);
<------><------>if (!stat(pwd, &pwd_stat) &&
<------><------>    pwd_stat.st_dev == cwd_stat.st_dev &&
<------><------>    pwd_stat.st_ino == cwd_stat.st_ino) {
<------><------><------>strlcpy(cwd, pwd, PATH_MAX);
<------><------>}
<------>}
<------>return cwd;
}
 
static const char *make_nonrelative_path(const char *path)
{
<------>static char buf[PATH_MAX + 1];
 
<------>if (is_absolute_path(path)) {
<------><------>if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
<------><------><------>die("Too long path: %.*s", 60, path);
<------>} else {
<------><------>const char *cwd = get_pwd_cwd();
<------><------>if (!cwd)
<------><------><------>die("Cannot determine the current working directory");
<------><------>if (snprintf(buf, PATH_MAX, "%s/%s", cwd, path) >= PATH_MAX)
<------><------><------>die("Too long path: %.*s", 60, path);
<------>}
<------>return buf;
}
 
char *system_path(const char *path)
{
<------>char *buf = NULL;
 
<------>if (is_absolute_path(path))
<------><------>return strdup(path);
 
<------>astrcatf(&buf, "%s/%s", subcmd_config.prefix, path);
 
<------>return buf;
}
 
const char *extract_argv0_path(const char *argv0)
{
<------>const char *slash;
 
<------>if (!argv0 || !*argv0)
<------><------>return NULL;
<------>slash = argv0 + strlen(argv0);
 
<------>while (argv0 <= slash && !is_dir_sep(*slash))
<------><------>slash--;
 
<------>if (slash >= argv0) {
<------><------>argv0_path = strndup(argv0, slash - argv0);
<------><------>return argv0_path ? slash + 1 : NULL;
<------>}
 
<------>return argv0;
}
 
void set_argv_exec_path(const char *exec_path)
{
<------>argv_exec_path = exec_path;
<------>/*
<------> * Propagate this setting to external programs.
<------> */
<------>setenv(subcmd_config.exec_path_env, exec_path, 1);
}
 
 
/* Returns the highest-priority location to look for subprograms. */
char *get_argv_exec_path(void)
{
<------>char *env;
 
<------>if (argv_exec_path)
<------><------>return strdup(argv_exec_path);
 
<------>env = getenv(subcmd_config.exec_path_env);
<------>if (env && *env)
<------><------>return strdup(env);
 
<------>return system_path(subcmd_config.exec_path);
}
 
static void add_path(char **out, const char *path)
{
<------>if (path && *path) {
<------><------>if (is_absolute_path(path))
<------><------><------>astrcat(out, path);
<------><------>else
<------><------><------>astrcat(out, make_nonrelative_path(path));
 
<------><------>astrcat(out, ":");
<------>}
}
 
void setup_path(void)
{
<------>const char *old_path = getenv("PATH");
<------>char *new_path = NULL;
<------>char *tmp = get_argv_exec_path();
 
<------>add_path(&new_path, tmp);
<------>add_path(&new_path, argv0_path);
<------>free(tmp);
 
<------>if (old_path)
<------><------>astrcat(&new_path, old_path);
<------>else
<------><------>astrcat(&new_path, "/usr/local/bin:/usr/bin:/bin");
 
<------>setenv("PATH", new_path, 1);
 
<------>free(new_path);
}
 
static const char **prepare_exec_cmd(const char **argv)
{
<------>int argc;
<------>const char **nargv;
 
<------>for (argc = 0; argv[argc]; argc++)
<------><------>; /* just counting */
<------>nargv = malloc(sizeof(*nargv) * (argc + 2));
 
<------>nargv[0] = subcmd_config.exec_name;
<------>for (argc = 0; argv[argc]; argc++)
<------><------>nargv[argc + 1] = argv[argc];
<------>nargv[argc + 1] = NULL;
<------>return nargv;
}
 
int execv_cmd(const char **argv) {
<------>const char **nargv = prepare_exec_cmd(argv);
 
<------>/* execvp() can only ever return if it fails */
<------>execvp(subcmd_config.exec_name, (char **)nargv);
 
<------>free(nargv);
<------>return -1;
}
 
 
int execl_cmd(const char *cmd,...)
{
<------>int argc;
<------>const char *argv[MAX_ARGS + 1];
<------>const char *arg;
<------>va_list param;
 
<------>va_start(param, cmd);
<------>argv[0] = cmd;
<------>argc = 1;
<------>while (argc < MAX_ARGS) {
<------><------>arg = argv[argc++] = va_arg(param, char *);
<------><------>if (!arg)
<------><------><------>break;
<------>}
<------>va_end(param);
<------>if (MAX_ARGS <= argc) {
<------><------>fprintf(stderr, " Error: too many args to run %s\n", cmd);
<------><------>return -1;
<------>}
 
<------>argv[argc] = NULL;
<------>return execv_cmd(argv);
}