Added ps draft

1 files changed, 365 insertions, 0 deletions

diff --git a/src/ps.c b/src/ps.c
new file mode 100644
index 0000000..bc090ec
--- /dev/null
+++ b/src/ps.c
@@ -0,0 +1,365 @@
+#define _POSIX_C_SOURCE 200809L
+#define _DEFAULT_SOURCE 1
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <stdbool.h>
+#include <errno.h>
+#include <dirent.h>
+#include <limits.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#define PROC_DIR "/proc"
+
+#define TASK_COMM_LEN 32
+
+static int page_size   = -1;
+static long clock_tick = -1;
+
+typedef enum
+{
+	FIELD_ARGS,
+	FIELD_COMM,
+	FIELD_PID,
+	FIELD_PPID,
+	FIELD_PGID,
+	FIELD_ETIME,
+	FIELD_TIME,
+	FIELD_GROUP,
+	FIELD_RGROUP,
+	FIELD_USER,
+	FIELD_RUSER,
+	FIELD_NICE,
+	FIELD_TTY,
+	FIELD_PCPU,
+	FIELD_VSZ,
+	FIELD_ADDR,
+	FIELD_ADDR,
+	FIELD_C,
+	FIELD_PRI,
+	FIELD_NI,
+	FIELD_ADDR,
+	FIELD_SZ,
+	FIELD_WCHAN,
+} t_field_id;
+
+typedef struct
+{
+	t_field_id id;
+	char       *specifier;
+	char       *header;
+	int        width;
+} t_field_info;
+
+static t_field_info field_infos[] = {
+	{FIELD_ARGS,   "args",   "COMMAND", 30},
+	{FIELD_COMM,   "comm",   "COMMAND", -1},
+	{FIELD_PID,    "pid",    "PID",     8},
+	{FIELD_PPID,   "ppid",   "PPID",    8},
+	{FIELD_PGID,   "pgid",   "PGID",    8},
+	{FIELD_ETIME,  "etime",  "ELAPSED", -1},
+	{FIELD_TIME,   "time",   "TIME",    -1},
+	{FIELD_GROUP,  "group",  "GROUP",   -1},
+	{FIELD_RGROUP, "rgroup", "RGROUP",  -1},
+	{FIELD_USER,   "user",   "USER",    -1},
+	{FIELD_RUSER,  "ruser",  "RUSER",   -1},
+	{FIELD_NICE,   "nice",   "NI",      -1},
+	{FIELD_TTY,    "tty",    "TT",      -1},
+	{FIELD_PCPU,   "pcpu",   "%CPU",    -1},
+	{FIELD_VSZ,    "vsz",    "VSZ",     -1},
+	{FIELD_FLAGS,  "f",      "F",       1},
+	{FIELD_STATE,  "s",      "S",       1},
+	{FIELD_C,      "c",      "C",       -1},
+	{FIELD_PRI,    "pri",    "PRI",     -1},
+	{FIELD_ADDR,   "addr",   "ADDR",    -1},
+	{FIELD_SZ,     "sz",     "SZ",      -1},
+	{FIELD_WCHAN,  "wchan",  "WCHAN",   -1},
+};
+
+
+t_field_info *filed_info_from_specifier(const char *specifier)
+{
+	for (size_t i = 0; i < sizeof(field_infos) / sizeof(t_field_info); i++)
+		if (strcmp(field_infos[i].specifier, specifier) == 0)
+			return (&field_infos[i]);
+	return (NULL);
+}
+
+static struct stat proc_statbuf;
+static char        *stat_file;
+static char        *cmdfile_file;
+
+void print_field_resource(t_field_info *field_info)
+{
+	switch (field_info->id)
+	{
+		case FIELD_ARGS:
+			snprintf(file_path, PATH_MAX, "%s/%d/cmdline", PROC_DIR, pid);
+			FILE *cmdline_file = fopen(file_path, "r");
+			if (cmdline_file == NULL)
+				return;
+			int c = EOF;
+			while ((c = fgetc(cmdline_file)) != EOF)
+				fputc(c, stdout);
+			break;
+
+		case FIELD_COMM:
+			char *closing_parent = strrchr(proc_stat.comm + 0, ')');
+			if (closing_parent != NULL)
+				*closing_parent = '\0';
+			printf("%s", proc_stat.comm + 1);
+			break;
+
+		case FIELD_PID:  printf("%*ld ", info.width, proc_stat.pid);  break;
+		case FIELD_PPID: printf("%*ld ", info.width, proc_stat.ppid); break;
+		case FIELD_PGID: printf("%*ld ", info.width, proc_stat.pgrp); break;
+
+		case FIELD_ETIME:
+			printf("%6lld ", /*current -*/ proc_stat.starttime / clock_tick);
+			break;
+		case FIELD_TIME:
+			printf("%6lld ", proc_stat.starttime / clock_tick);
+			break;
+
+		case FIELD_GROUP:
+			break;
+		case FIELD_RGROUP:
+			break;
+		case FIELD_USER:
+			printf("%6d ", proc_statbuf.st_uid);
+			break;
+		case FIELD_RUSER:
+			break;
+
+		case FIELD_NICE:
+			printf("%3ld ", proc_stat.nice);
+			break;
+		case FIELD_PRI:
+			printf("%3ld ", proc_stat.priority);
+			break;
+
+		case FIELD_TTY:
+			printf("%6d ", proc_stat.tty_nr);
+			break;
+		case FIELD_PCPU:
+			break;
+		case FIELD_VSZ:
+			printf("%5ld ", proc_stat.vsize / page_size);
+			break;
+		case FIELD_ADDR:
+			break;
+		case FIELD_FLAGS:
+			printf("%o ", 0); //proc_stat.flags,
+			break;
+		case FIELD_STATE:
+			printf("%c ", proc_stat.state);
+			break;
+
+		case FIELD_C:
+			break;
+		case FIELD_SZ:
+			break;
+
+		case FIELD_WCHAN:
+			printf("%4ld ", proc_stat.wchan);
+			break;
+
+		default:
+			exit(1);
+	}
+}
+
+char full_format[]    = "user pid ppid c stime tty time args";
+char long_format[]    = "f s user pid ppid c pri ni addr sz wchan tty time cmd";
+char default_format[] = "pid tty time cmd";
+
+size_t         fields_size = 0;
+t_field_info **field_infos = NULL;
+
+void field_infos_from_format(char *format)
+{
+	size_t i;
+
+	for (i = 0; format[i] != '\0'; i++)
+		if (isspace(format[i]) && isspace(format[i + 1]))
+			exit(1);
+
+	fields_size = 0;
+	for (i = 0; format[i] != '\0'; i++)
+		if (isspace(format[i]))
+			fields_size++;
+
+	field_infos = malloc(fields_size * sizeof(t_field_info*));
+	if (field_infos == NULL)
+		exit(1);
+
+	i = 0;
+	char *specifier = NULL;
+	while ((specifier = strsep(&format, " ,")) != NULL)
+	{
+		field_infos[i] = field_info_from_specifier(specifier);
+		if (field_infos[i] == NULL)
+			exit(1);
+		i++;
+	}
+}
+
+void print_header(void)
+{
+	for (size_t i = 0; i < fields_size; i++)
+		printf("%*s ", field_infos[i].width, field_infos[i].header);
+}
+
+typedef struct
+{
+	pid_t              pid;
+	char               comm[TASK_COMM_LEN];
+	char               state;
+	pid_t              ppid;
+	pid_t              pgrp;
+	int                session;
+	int                tty_nr;
+	int                tpgid;
+	unsigned int       flags;
+	unsigned long      minflt;
+	unsigned long      cminflt;
+	unsigned long      majflt;
+	unsigned long      cmajflt;
+	unsigned long      utime;
+	unsigned long      stime;
+	long               cutime;
+	long               cstime;
+	long               priority;
+	long               nice;
+	long               num_threads;
+	long               itrealvalue;
+	unsigned long long starttime;
+	unsigned long      vsize;
+	long               rss;
+	unsigned long      rsslim;
+	unsigned long      startcode;
+	unsigned long      endcode;
+	unsigned long      startstack;
+	unsigned long      kstkesp;
+	unsigned long      kstkeip;
+	unsigned long      signal;
+	unsigned long      blocked;
+	unsigned long      sigignore;
+	unsigned long      sigcatch;
+	unsigned long      wchan;
+	unsigned long      nswap;
+	unsigned long      cnswap;
+	int                exit_signal;
+	int                processor;
+	unsigned int       rt_priority;
+	unsigned long      delayacct_blkio_ticks;
+	unsigned long      guest_time;
+	long               cguest_time;
+	unsigned long      end_data;
+	unsigned long      start_brk;
+	unsigned long      arg_start;
+	unsigned long      arg_end;
+	unsigned long      env_start;
+	unsigned long      env_end;
+	int                exit_code;
+} t_proc_stat;
+
+int main(int argc, char **argv)
+{
+	field_infos_from_format(default_format);
+
+	free(field_infos);
+	return;
+
+
+	page_size = getpagesize();
+	clock_tick = sysconf(_SC_CLK_TCK);
+
+	DIR *proc_dir = opendir(PROC_DIR);
+	if (proc_dir == NULL)
+		exit(1);
+	struct dirent *proc_dir_entry = NULL;
+	while ((proc_dir_entry = readdir(proc_dir)) != NULL)
+	{
+		pid_t pid = 0;
+		if (sscanf(proc_dir_entry->d_name, "%d", &pid) != 1)
+			continue;
+
+		char file_path[PATH_MAX + 1] = {'\0'};
+		snprintf(file_path, PATH_MAX, "%s/%d/stat", PROC_DIR, pid);
+		FILE *stat_file = fopen(file_path, "r");
+		if (stat_file == NULL)
+			continue;
+
+		t_proc_stat proc_stat;
+		fscanf(
+			stat_file,
+			"%d %s %c %d %d %d %d %d %u %lu %lu %lu %lu %lu %lu %ld %ld %ld %ld %ld %ld "
+			"%llu %lu %ld %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %d %d %u "
+			"%llu %lu %ld %lu %lu %lu %lu %lu %lu %d",
+			&proc_stat.pid,
+			&proc_stat.comm,
+			&proc_stat.state,
+			&proc_stat.ppid,
+			&proc_stat.pgrp,
+			&proc_stat.session,
+			&proc_stat.tty_nr,
+			&proc_stat.tpgid,
+			&proc_stat.flags,
+			&proc_stat.minflt,
+			&proc_stat.cminflt,
+			&proc_stat.majflt,
+			&proc_stat.cmajflt,
+			&proc_stat.utime,
+			&proc_stat.stime,
+			&proc_stat.cutime,
+			&proc_stat.cstime,
+			&proc_stat.priority,
+			&proc_stat.nice,
+			&proc_stat.num_threads,
+			&proc_stat.itrealvalue,
+			&proc_stat.starttime,
+			&proc_stat.vsize,
+			&proc_stat.rss,
+			&proc_stat.rsslim,
+			&proc_stat.startcode,
+			&proc_stat.endcode,
+			&proc_stat.startstack,
+			&proc_stat.kstkesp,
+			&proc_stat.kstkeip,
+			&proc_stat.signal,
+			&proc_stat.blocked,
+			&proc_stat.sigignore,
+			&proc_stat.sigcatch,
+			&proc_stat.wchan,
+			&proc_stat.nswap,
+			&proc_stat.cnswap,
+			&proc_stat.exit_signal,
+			&proc_stat.processor,
+			&proc_stat.rt_priority,
+			&proc_stat.delayacct_blkio_ticks,
+			&proc_stat.guest_time,
+			&proc_stat.cguest_time,
+			&proc_stat.end_data,
+			&proc_stat.start_brk,
+			&proc_stat.arg_start,
+			&proc_stat.arg_end,
+			&proc_stat.env_start,
+			&proc_stat.env_end,
+			&proc_stat.exit_code
+		);
+
+		struct stat statbuf;
+		if (stat(file_path, &statbuf) == -1)
+			continue;
+
+		fputc('\n', stdout);
+		break;
+	}
+
+	return 0;
+}