* - Command history (up/down arrow keys)
* - Pipes (cmd1 | cmd2 | cmd3)
* - Redirections (< > >>)
+ * - Operators: ; && || &
+ * - Job control: CTRL+C (SIGINT), CTRL+Z (SIGTSTP), background (&)
* - Builtins: cd, exit, echo, export, unset, set, pwd, type
* - PATH-based command resolution
* - Quote handling (single and double quotes)
#include <fcntl.h>
#include <dirent.h>
#include <termios.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include <sys/wait.h>
static struct termios orig_termios;
return cmd;
}
+/* ---- Helper: set foreground process group on controlling TTY ---- */
+
+static void set_fg_pgrp(int pgrp) {
+ ioctl(STDIN_FILENO, TIOCSPGRP, &pgrp);
+}
+
/* ---- Run a single simple command ---- */
+static int bg_flag = 0; /* set by caller when trailing & detected */
+
static void run_simple(char* cmd) {
/* Expand variables */
char expanded[LINE_MAX];
if (pid < 0) { fprintf(stderr, "sh: fork failed\n"); return; }
if (pid == 0) {
- /* child */
+ /* child: own process group, restore default signals */
+ setpgid(0, 0);
+ struct sigaction sa;
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_handler = (uintptr_t)SIG_DFL;
+ sigaction(SIGINT, &sa, NULL);
+ sigaction(SIGTSTP, &sa, NULL);
+ sigaction(SIGQUIT, &sa, NULL);
+
if (redir_in) {
int fd = open(redir_in, O_RDONLY);
if (fd >= 0) { dup2(fd, 0); close(fd); }
_exit(127);
}
- /* parent waits */
- int st;
- waitpid(pid, &st, 0);
- last_status = st;
+ /* parent */
+ setpgid(pid, pid);
+
+ if (bg_flag) {
+ /* Background: don't wait, print job info */
+ printf("[bg] %d\n", pid);
+ last_status = 0;
+ } else {
+ /* Foreground: make child the fg process group, wait, then restore */
+ set_fg_pgrp(pid);
+ int st;
+ waitpid(pid, &st, 0);
+ set_fg_pgrp(getpgrp());
+ last_status = st;
+ }
goto restore_redir;
restore_redir:
if (*p == '\'' && !in_dq) in_sq = !in_sq;
else if (*p == '"' && !in_sq) in_dq = !in_dq;
else if (*p == '|' && !in_sq && !in_dq && ncmds < 7) {
+ if (*(p + 1) == '|') { p++; continue; } /* skip || */
*p = '\0';
cmds[++ncmds] = p + 1;
}
/* Multi-stage pipeline */
int prev_rd = -1;
int pids[8];
+ int pgid = 0; /* pipeline process group = first child's PID */
for (int i = 0; i < ncmds; i++) {
int pfd[2] = {-1, -1};
if (pids[i] < 0) { fprintf(stderr, "sh: fork failed\n"); return; }
if (pids[i] == 0) {
+ /* child: join pipeline process group, restore signals */
+ int mypgid = pgid ? pgid : getpid();
+ setpgid(0, mypgid);
+ struct sigaction sa;
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_handler = (uintptr_t)SIG_DFL;
+ sigaction(SIGINT, &sa, NULL);
+ sigaction(SIGTSTP, &sa, NULL);
+ sigaction(SIGQUIT, &sa, NULL);
+
if (prev_rd >= 0) { dup2(prev_rd, 0); close(prev_rd); }
if (pfd[1] >= 0) { dup2(pfd[1], 1); close(pfd[1]); }
if (pfd[0] >= 0) close(pfd[0]);
_exit(127);
}
- /* parent */
+ /* parent: set pipeline pgid */
+ if (i == 0) pgid = pids[0];
+ setpgid(pids[i], pgid);
+
if (prev_rd >= 0) close(prev_rd);
if (pfd[1] >= 0) close(pfd[1]);
prev_rd = pfd[0];
if (prev_rd >= 0) close(prev_rd);
- /* Wait for all children */
- for (int i = 0; i < ncmds; i++) {
- int st;
- waitpid(pids[i], &st, 0);
- if (i == ncmds - 1) last_status = st;
+ if (!bg_flag) {
+ /* Foreground pipeline: make it fg, wait, restore */
+ set_fg_pgrp(pgid);
+ for (int i = 0; i < ncmds; i++) {
+ int st;
+ waitpid(pids[i], &st, 0);
+ if (i == ncmds - 1) last_status = st;
+ }
+ set_fg_pgrp(getpgrp());
+ } else {
+ printf("[bg] %d\n", pgid);
+ last_status = 0;
}
}
-/* ---- Process a command line (handle ; and &&) ---- */
+/* ---- Process a command line (handle ;, &&, ||, &) ---- */
+
+enum { OP_NONE = 0, OP_SEMI, OP_AND, OP_OR, OP_BG };
static void process_line(char* input) {
- /* Split on ';' */
char* p = input;
+
while (*p) {
- /* skip leading whitespace */
while (*p == ' ' || *p == '\t') p++;
if (*p == '\0') break;
+ /* Find the next operator outside quotes */
char* start = p;
int in_sq = 0, in_dq = 0;
+ int op = OP_NONE;
+
while (*p) {
- if (*p == '\'' && !in_dq) in_sq = !in_sq;
- else if (*p == '"' && !in_sq) in_dq = !in_dq;
- else if (*p == ';' && !in_sq && !in_dq) break;
+ if (*p == '\'' && !in_dq) { in_sq = !in_sq; p++; continue; }
+ if (*p == '"' && !in_sq) { in_dq = !in_dq; p++; continue; }
+ if (in_sq || in_dq) { p++; continue; }
+
+ if (*p == '&' && *(p + 1) == '&') {
+ *p = '\0'; p += 2; op = OP_AND; break;
+ }
+ if (*p == '|' && *(p + 1) == '|') {
+ *p = '\0'; p += 2; op = OP_OR; break;
+ }
+ if (*p == ';') {
+ *p = '\0'; p++; op = OP_SEMI; break;
+ }
+ if (*p == '&') {
+ *p = '\0'; p++; op = OP_BG; break;
+ }
p++;
}
- char saved = *p;
- if (*p) *p++ = '\0';
- if (start[0] != '\0')
- run_pipeline(start);
+ /* Trim leading whitespace from segment */
+ while (*start == ' ' || *start == '\t') start++;
+ if (*start != '\0') {
+ if (op == OP_BG) {
+ bg_flag = 1;
+ run_pipeline(start);
+ bg_flag = 0;
+ } else {
+ bg_flag = 0;
+ run_pipeline(start);
+ }
+ }
+
+ /* For &&: skip remaining commands if last failed */
+ if (op == OP_AND && last_status != 0) {
+ /* Skip until we hit || or ; or & or end */
+ while (*p) {
+ while (*p == ' ' || *p == '\t') p++;
+ if (*p == '\0') break;
+ int skip_sq = 0, skip_dq = 0;
+ while (*p) {
+ if (*p == '\'' && !skip_dq) { skip_sq = !skip_sq; p++; continue; }
+ if (*p == '"' && !skip_sq) { skip_dq = !skip_dq; p++; continue; }
+ if (skip_sq || skip_dq) { p++; continue; }
+ if (*p == '|' && *(p + 1) == '|') break;
+ if (*p == ';') break;
+ if (*p == '&' && *(p + 1) != '&') break;
+ if (*p == '&' && *(p + 1) == '&') { p += 2; continue; }
+ p++;
+ }
+ break;
+ }
+ }
- if (saved == '\0') break;
+ /* For ||: skip remaining commands if last succeeded */
+ if (op == OP_OR && last_status == 0) {
+ while (*p) {
+ while (*p == ' ' || *p == '\t') p++;
+ if (*p == '\0') break;
+ int skip_sq = 0, skip_dq = 0;
+ while (*p) {
+ if (*p == '\'' && !skip_dq) { skip_sq = !skip_sq; p++; continue; }
+ if (*p == '"' && !skip_sq) { skip_dq = !skip_dq; p++; continue; }
+ if (skip_sq || skip_dq) { p++; continue; }
+ if (*p == '&' && *(p + 1) == '&') break;
+ if (*p == ';') break;
+ if (*p == '&' && *(p + 1) != '&') break;
+ if (*p == '|' && *(p + 1) == '|') { p += 2; continue; }
+ p++;
+ }
+ break;
+ }
+ }
}
}
if (!var_get("HOME"))
var_set("HOME", "/", 1);
+ /* Job control: put shell in its own process group and make it fg */
+ setpgid(0, 0);
+ set_fg_pgrp(getpgrp());
+
+ /* Ignore job control signals in the shell itself */
+ struct sigaction sa_ign;
+ memset(&sa_ign, 0, sizeof(sa_ign));
+ sa_ign.sa_handler = (uintptr_t)SIG_IGN;
+ sigaction(SIGINT, &sa_ign, NULL);
+ sigaction(SIGTSTP, &sa_ign, NULL);
+ sigaction(SIGQUIT, &sa_ign, NULL);
+
tty_raw_mode();
print_prompt();
projects / AdrOS.git / commitdiff