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complement lab03

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yenru0
2025-11-24 03:03:35 +09:00
parent 3e87f2c37d
commit 1c50fbd315
1 changed files with 351 additions and 272 deletions
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217
labs/03_shlab/tsh.c
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@@ -4,21 +4,21 @@
* Name: <fill in>
* Student id: <fill in>
*/
#include <ctype.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <unistd.h>
/* Misc manifest constants */
#define MAXLINE 1024 /* max line size */
#define MAXARGS 128 /* max args on a command line */
#define MAXJOBS 16 /* max jobs at any point in time */
#define MAXJID 1<<16 /* max job ID */
#define MAXJID 1 << 16 /* max job ID */
/* Job states */
#define UNDEF 0 /* undefined */
@@ -52,7 +52,6 @@ struct job_t { /* The job struct */
struct job_t jobs[MAXJOBS]; /* The job list */
/* End global variables */
/* Function prototypes */
/*----------------------------------------------------------------------------
@@ -94,8 +93,7 @@ handler_t *Signal(int signum, handler_t *handler);
/*
* main - The shell's main routine
*/
int main(int argc, char **argv)
{
int main(int argc, char **argv) {
char c;
char cmdline[MAXLINE];
int emit_prompt = 1; /* emit prompt (default) */
@@ -169,9 +167,30 @@ int main(int argc, char **argv)
* background children don't receive SIGINT (SIGTSTP) from the kernel
* when we type ctrl-c (ctrl-z) at the keyboard.
*/
void eval(char *cmdline)
{
return;
void eval(char *cmdline) {
pid_t pid;
char *argv[MAXARGS];
int bg = parseline(cmdline, argv);
if (argv[0] && !builtin_cmd(argv)) {
if ((pid = fork()) == 0) {// Child process
setpgid(0, 0); // Set new process group
if (execve(argv[0], argv, environ) < 0) {
printf("%s: Command not found\n", argv[0]);
exit(0);
}
}
if (!bg) {// Foreground job
addjob(jobs, pid, FG, cmdline);
waitfg(pid);
} else {// Background job
addjob(jobs, pid, BG, cmdline);
fprintf(stderr, "[%d] (%d) %s", pid2jid(pid), pid, cmdline);
}
}
}
/*
@@ -181,8 +200,7 @@ void eval(char *cmdline)
* argument. Return true if the user has requested a BG job, false if
* the user has requested a FG job.
*/
int parseline(const char *cmdline, char **argv)
{
int parseline(const char *cmdline, char **argv) {
static char array[MAXLINE]; /* holds local copy of command line */
char *buf = array; /* ptr that traverses command line */
char *delim; /* points to first space delimiter */
@@ -190,7 +208,7 @@ int parseline(const char *cmdline, char **argv)
int bg; /* background job? */
strcpy(buf, cmdline);
buf[strlen(buf)-1] = ' '; /* replace trailing '\n' with space */
buf[strlen(buf) - 1] = ' '; /* replace trailing '\n' with space */
while (*buf && (*buf == ' ')) /* ignore leading spaces */
buf++;
@@ -199,8 +217,7 @@ int parseline(const char *cmdline, char **argv)
if (*buf == '\'') {
buf++;
delim = strchr(buf, '\'');
}
else {
} else {
delim = strchr(buf, ' ');
}
@@ -214,8 +231,7 @@ int parseline(const char *cmdline, char **argv)
if (*buf == '\'') {
buf++;
delim = strchr(buf, '\'');
}
else {
} else {
delim = strchr(buf, ' ');
}
}
@@ -225,7 +241,7 @@ int parseline(const char *cmdline, char **argv)
return 1;
/* should the job run in the background? */
if ((bg = (*argv[argc-1] == '&')) != 0) {
if ((bg = (*argv[argc - 1] == '&')) != 0) {
argv[--argc] = NULL;
}
return bg;
@@ -235,24 +251,81 @@ int parseline(const char *cmdline, char **argv)
* builtin_cmd - If the user has typed a built-in command then execute
* it immediately.
*/
int builtin_cmd(char **argv)
{
return 0; /* not a builtin command */
int builtin_cmd(char **argv) {
// Built-in-commands: jobs, bg, fg, quit
if (!strcmp(argv[0], "quit")) {
exit(0);
} else if (!strcmp(argv[0], "jobs")) {
listjobs(jobs);
return 1;
} else if (!strcmp(argv[0], "bg") || !strcmp(argv[0], "fg")) {
do_bgfg(argv);
return 1;
}
return 0;
}
/*
* do_bgfg - Execute the builtin bg and fg commands
*/
void do_bgfg(char **argv)
{
void do_bgfg(char **argv) {
struct job_t *job = NULL;
pid_t pid;
int jid;
if (argv[1] == NULL) {
printf("%s command requires PID or %%jobid argument\n", argv[0]);
return;
}
if (argv[1][0] == '%') {
if (sscanf(&argv[1][1], "%d", &jid) != 1) {
printf("%s: argument must be a PID or %%jobid\n", argv[0]);
return;
}
job = getjobjid(jobs, jid);
if (job == NULL) {
printf("%s: No such job\n", argv[1]);
return;
}
} else if (isdigit((unsigned char) argv[1][0])) {
if (sscanf(argv[1], "%d", &pid) != 1) {
printf("%s: argument must be a PID or %%jobid\n", argv[0]);
return;
}
job = getjobpid(jobs, pid);
if (job == NULL) {
printf("(%s): No such process\n", argv[1]);
return;
}
} else {
printf("%s: argument must be a PID or %%jobid\n", argv[0]);
return;
}
pid = job->pid;
if (!strcmp(argv[0], "bg")) {
job->state = BG;
if (kill(-pid, SIGCONT) < 0)
unix_error("kill (SIGCONT) error");
printf("[%d] (%d) %s", job->jid, job->pid, job->cmdline);
} else { /* fg */
job->state = FG;
if (kill(-pid, SIGCONT) < 0)
unix_error("kill (SIGCONT) error");
waitfg(pid);
}
}
/*
* waitfg - Block until process pid is no longer the foreground process
*/
void waitfg(pid_t pid)
{
void waitfg(pid_t pid) {
while (pid == fgpid(jobs)) {
sleep(1);
}
return;
}
@@ -267,9 +340,27 @@ void waitfg(pid_t pid)
* available zombie children, but doesn't wait for any other
* currently running children to terminate.
*/
void sigchld_handler(int sig)
{
return;
void sigchld_handler(int sig) {
int olderrno = errno;
pid_t pid;
int status;
while ((pid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) {
if (WIFEXITED(status)) {
deletejob(jobs, pid);
} else if (WIFSIGNALED(status)) {
fprintf(stderr, "Job [%d] (%d) terminated by signal %d\n", pid2jid(pid), pid, WTERMSIG(status));
deletejob(jobs, pid);
} else if (WIFSTOPPED(status)) {
struct job_t *job = getjobpid(jobs, pid);
if (job != NULL) {
job->state = ST;
fprintf(stderr, "Job [%d] (%d) stopped by signal %d\n", job->jid, pid, WSTOPSIG(status));
}
}
}
errno = olderrno;
}
/*
@@ -277,9 +368,11 @@ void sigchld_handler(int sig)
* user types ctrl-c at the keyboard. Catch it and send it along
* to the foreground job.
*/
void sigint_handler(int sig)
{
return;
void sigint_handler(int sig) {
pid_t pid;
if ((pid = fgpid(jobs)) > 0) {
kill(-pid, SIGINT);
}
}
/*
@@ -287,9 +380,11 @@ void sigint_handler(int sig)
* the user types ctrl-z at the keyboard. Catch it and suspend the
* foreground job by sending it a SIGTSTP.
*/
void sigtstp_handler(int sig)
{
return;
void sigtstp_handler(int sig) {
pid_t pid;
if ((pid = fgpid(jobs)) > 0) {
kill(-pid, SIGTSTP);
}
}
/*********************
@@ -301,8 +396,7 @@ void sigtstp_handler(int sig)
**********************************************/
/* clearjob - Clear the entries in a job struct */
void clearjob(struct job_t *job)
{
void clearjob(struct job_t *job) {
job->pid = 0;
job->jid = 0;
job->state = UNDEF;
@@ -310,8 +404,7 @@ void clearjob(struct job_t *job)
}
/* initjobs - Initialize the job list */
void initjobs(struct job_t *jobs)
{
void initjobs(struct job_t *jobs) {
int i;
for (i = 0; i < MAXJOBS; i++)
@@ -319,9 +412,8 @@ void initjobs(struct job_t *jobs)
}
/* maxjid - Returns largest allocated job ID */
int maxjid(struct job_t *jobs)
{
int i, max=0;
int maxjid(struct job_t *jobs) {
int i, max = 0;
for (i = 0; i < MAXJOBS; i++)
if (jobs[i].jid > max)
@@ -330,8 +422,7 @@ int maxjid(struct job_t *jobs)
}
/* addjob - Add a job to the job list */
int addjob(struct job_t *jobs, pid_t pid, int state, char *cmdline)
{
int addjob(struct job_t *jobs, pid_t pid, int state, char *cmdline) {
int i;
if (pid < 1)
@@ -345,7 +436,7 @@ int addjob(struct job_t *jobs, pid_t pid, int state, char *cmdline)
if (nextjid > MAXJOBS)
nextjid = 1;
strcpy(jobs[i].cmdline, cmdline);
if(verbose){
if (verbose) {
printf("Added job [%d] %d %s\n", jobs[i].jid, jobs[i].pid, jobs[i].cmdline);
}
return 1;
@@ -356,8 +447,7 @@ int addjob(struct job_t *jobs, pid_t pid, int state, char *cmdline)
}
/* deletejob - Delete a job whose PID=pid from the job list */
int deletejob(struct job_t *jobs, pid_t pid)
{
int deletejob(struct job_t *jobs, pid_t pid) {
int i;
if (pid < 1)
@@ -366,7 +456,7 @@ int deletejob(struct job_t *jobs, pid_t pid)
for (i = 0; i < MAXJOBS; i++) {
if (jobs[i].pid == pid) {
clearjob(&jobs[i]);
nextjid = maxjid(jobs)+1;
nextjid = maxjid(jobs) + 1;
return 1;
}
}
@@ -374,8 +464,7 @@ int deletejob(struct job_t *jobs, pid_t pid)
}
/* fgpid - Return PID of current foreground job, 0 if no such job */
pid_t fgpid(struct job_t *jobs)
{
pid_t fgpid(struct job_t *jobs) {
int i;
for (i = 0; i < MAXJOBS; i++)
@@ -385,8 +474,7 @@ pid_t fgpid(struct job_t *jobs)
}
/* getjobpid - Find a job (by PID) on the job list */
struct job_t *getjobpid(struct job_t *jobs, pid_t pid)
{
struct job_t *getjobpid(struct job_t *jobs, pid_t pid) {
int i;
if (pid < 1)
@@ -398,8 +486,7 @@ struct job_t *getjobpid(struct job_t *jobs, pid_t pid)
}
/* getjobjid - Find a job (by JID) on the job list */
struct job_t *getjobjid(struct job_t *jobs, int jid)
{
struct job_t *getjobjid(struct job_t *jobs, int jid) {
int i;
if (jid < 1)
@@ -411,8 +498,7 @@ struct job_t *getjobjid(struct job_t *jobs, int jid)
}
/* pid2jid - Map process ID to job ID */
int pid2jid(pid_t pid)
{
int pid2jid(pid_t pid) {
int i;
if (pid < 1)
@@ -425,8 +511,7 @@ int pid2jid(pid_t pid)
}
/* listjobs - Print the job list */
void listjobs(struct job_t *jobs)
{
void listjobs(struct job_t *jobs) {
int i;
for (i = 0; i < MAXJOBS; i++) {
@@ -454,7 +539,6 @@ void listjobs(struct job_t *jobs)
* end job list helper routines
******************************/
/***********************
* Other helper routines
***********************/
@@ -462,8 +546,7 @@ void listjobs(struct job_t *jobs)
/*
* usage - print a help message
*/
void usage(void)
{
void usage(void) {
printf("Usage: shell [-hvp]\n");
printf(" -h print this message\n");
printf(" -v print additional diagnostic information\n");
@@ -474,8 +557,7 @@ void usage(void)
/*
* unix_error - unix-style error routine
*/
void unix_error(char *msg)
{
void unix_error(char *msg) {
fprintf(stdout, "%s: %s\n", msg, strerror(errno));
exit(1);
}
@@ -483,8 +565,7 @@ void unix_error(char *msg)
/*
* app_error - application-style error routine
*/
void app_error(char *msg)
{
void app_error(char *msg) {
fprintf(stdout, "%s\n", msg);
exit(1);
}
@@ -492,8 +573,7 @@ void app_error(char *msg)
/*
* Signal - wrapper for the sigaction function
*/
handler_t *Signal(int signum, handler_t *handler)
{
handler_t *Signal(int signum, handler_t *handler) {
struct sigaction action, old_action;
action.sa_handler = handler;
@@ -509,8 +589,7 @@ handler_t *Signal(int signum, handler_t *handler)
* sigquit_handler - The driver program can gracefully terminate the
* child shell by sending it a SIGQUIT signal.
*/
void sigquit_handler(int sig)
{
void sigquit_handler(int sig) {
printf("Terminating after receipt of SIGQUIT signal\n");
exit(1);
}