int process_start(const char* pidFilename)
{
pid_t pid;
int result;
char cmdline[MAX_PATH_SIZE];
char cmdfile[MAX_PATH_SIZE];
char argv0[MAX_PATH_SIZE];
int64_t cmdsz;
if ((result=get_pid_from_file(pidFilename, &pid)) != 0) {
if (result == ENOENT) {
return 0;
}
else {
fprintf(stderr, "get pid from file: %s fail, " \
"errno: %d, error info: %s\n",
pidFilename, result, strerror(result));
return result;
}
}
if (kill(pid, 0) == 0) {
const char *exename1, *exename2;
cmdsz = sizeof(cmdline);
cmdline[cmdsz-1] = argv0[cmdsz-1] = '\0';
sprintf(cmdfile, "/proc/%d/cmdline", pid);
if ((result=getFileContentEx(cmdfile, cmdline, 0, &cmdsz)) != 0) {
fprintf(stderr, "read file %s failed. %d %s\n",
cmdfile, errno, strerror(errno));
return result;
}
cmdsz = sizeof(argv0);
sprintf(cmdfile, "/proc/%d/cmdline", getpid());
if ((result=getFileContentEx(cmdfile, argv0, 0, &cmdsz)) != 0) {
fprintf(stderr, "read file %s failed. %d %s\n",
cmdfile, errno, strerror(errno));
return result;
}
exename1 = process_get_exename(cmdline);
exename2 = process_get_exename(argv0);
if (strcmp(exename1, exename2) == 0) {
fprintf(stderr, "process %s already running, pid: %d\n",
argv0, (int)pid);
return EEXIST;
}
return 0;
}
else if (errno == ENOENT || errno == ESRCH) {
return 0;
}
else {
result = errno != 0 ? errno : EPERM;
fprintf(stderr, "kill pid: %d fail, errno: %d, error info: %s\n",
(int)pid, errno, strerror(errno));
return result;
}
}
int get_pid_from_file(const char *pidFilename, pid_t *pid)
{
char buff[32];
int64_t file_size;
int result;
if (access(pidFilename, F_OK) != 0) {
return errno != 0 ? errno : EPERM;
}
file_size = sizeof(buff) - 1;
if ((result=getFileContentEx(pidFilename, buff, 0, &file_size)) != 0) {
return result;
}
*(buff + file_size) = '\0';
*pid = strtol(buff, NULL, 10);
if (*pid == 0) {
return EINVAL;
}
return 0;
}
int get_processes(struct fast_process_info **processes, int *count)
{
const char *dirname = "/proc";
char filename[128];
char buff[4096];
DIR *dir;
struct dirent *ent;
FastProcessArray proc_array;
int64_t bytes;
int result;
int len;
int i;
dir = opendir(dirname);
if (dir == NULL)
{
*count = 0;
*processes = NULL;
logError("file: "__FILE__", line: %d, "
"call opendir %s fail, "
"errno: %d, error info: %s",
__LINE__, dirname, errno, STRERROR(errno));
return errno != 0 ? errno : EPERM;
}
result = 0;
proc_array.procs = NULL;
proc_array.alloc_size = 0;
proc_array.count = 0;
while ((ent=readdir(dir)) != NULL)
{
len = strlen(ent->d_name);
for (i=0; i<len; i++)
{
if (!(ent->d_name[i] >= '0' && ent->d_name[i] <= '9'))
{
break;
}
}
if (i < len) //not digital string
{
continue;
}
sprintf(filename, "%s/%s/stat", dirname, ent->d_name);
bytes = sizeof(buff);
if (getFileContentEx(filename, buff, 0, &bytes) != 0)
{
continue;
}
if ((result=check_process_capacity(&proc_array)) != 0)
{
break;
}
parse_proc_stat(buff, bytes, proc_array.procs + proc_array.count);
proc_array.count++;
}
closedir(dir);
*count = proc_array.count;
*processes = proc_array.procs;
return result;
}
