first commit

This commit is contained in:
2025-02-21 08:39:49 +08:00
commit 6aa7311ce6
80 changed files with 12752 additions and 0 deletions

44
user/cat.c Normal file
View File

@@ -0,0 +1,44 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "kernel/fcntl.h"
#include "user/user.h"
char buf[512];
void
cat(int fd)
{
int n;
while((n = read(fd, buf, sizeof(buf))) > 0) {
if (write(1, buf, n) != n) {
fprintf(2, "cat: write error\n");
exit(1);
}
}
if(n < 0){
fprintf(2, "cat: read error\n");
exit(1);
}
}
int
main(int argc, char *argv[])
{
int fd, i;
if(argc <= 1){
cat(0);
exit(0);
}
for(i = 1; i < argc; i++){
if((fd = open(argv[i], O_RDONLY)) < 0){
fprintf(2, "cat: cannot open %s\n", argv[i]);
exit(1);
}
cat(fd);
close(fd);
}
exit(0);
}

19
user/echo.c Normal file
View File

@@ -0,0 +1,19 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
int
main(int argc, char *argv[])
{
int i;
for(i = 1; i < argc; i++){
write(1, argv[i], strlen(argv[i]));
if(i + 1 < argc){
write(1, " ", 1);
} else {
write(1, "\n", 1);
}
}
exit(0);
}

56
user/forktest.c Normal file
View File

@@ -0,0 +1,56 @@
// Test that fork fails gracefully.
// Tiny executable so that the limit can be filling the proc table.
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
#define N 1000
void
print(const char *s)
{
write(1, s, strlen(s));
}
void
forktest(void)
{
int n, pid;
print("fork test\n");
for(n=0; n<N; n++){
pid = fork();
if(pid < 0)
break;
if(pid == 0)
exit(0);
}
if(n == N){
print("fork claimed to work N times!\n");
exit(1);
}
for(; n > 0; n--){
if(wait(0) < 0){
print("wait stopped early\n");
exit(1);
}
}
if(wait(0) != -1){
print("wait got too many\n");
exit(1);
}
print("fork test OK\n");
}
int
main(void)
{
forktest();
exit(0);
}

107
user/grep.c Normal file
View File

@@ -0,0 +1,107 @@
// Simple grep. Only supports ^ . * $ operators.
#include "kernel/types.h"
#include "kernel/stat.h"
#include "kernel/fcntl.h"
#include "user/user.h"
char buf[1024];
int match(char*, char*);
void
grep(char *pattern, int fd)
{
int n, m;
char *p, *q;
m = 0;
while((n = read(fd, buf+m, sizeof(buf)-m-1)) > 0){
m += n;
buf[m] = '\0';
p = buf;
while((q = strchr(p, '\n')) != 0){
*q = 0;
if(match(pattern, p)){
*q = '\n';
write(1, p, q+1 - p);
}
p = q+1;
}
if(m > 0){
m -= p - buf;
memmove(buf, p, m);
}
}
}
int
main(int argc, char *argv[])
{
int fd, i;
char *pattern;
if(argc <= 1){
fprintf(2, "usage: grep pattern [file ...]\n");
exit(1);
}
pattern = argv[1];
if(argc <= 2){
grep(pattern, 0);
exit(0);
}
for(i = 2; i < argc; i++){
if((fd = open(argv[i], O_RDONLY)) < 0){
printf("grep: cannot open %s\n", argv[i]);
exit(1);
}
grep(pattern, fd);
close(fd);
}
exit(0);
}
// Regexp matcher from Kernighan & Pike,
// The Practice of Programming, Chapter 9, or
// https://www.cs.princeton.edu/courses/archive/spr09/cos333/beautiful.html
int matchhere(char*, char*);
int matchstar(int, char*, char*);
int
match(char *re, char *text)
{
if(re[0] == '^')
return matchhere(re+1, text);
do{ // must look at empty string
if(matchhere(re, text))
return 1;
}while(*text++ != '\0');
return 0;
}
// matchhere: search for re at beginning of text
int matchhere(char *re, char *text)
{
if(re[0] == '\0')
return 1;
if(re[1] == '*')
return matchstar(re[0], re+2, text);
if(re[0] == '$' && re[1] == '\0')
return *text == '\0';
if(*text!='\0' && (re[0]=='.' || re[0]==*text))
return matchhere(re+1, text+1);
return 0;
}
// matchstar: search for c*re at beginning of text
int matchstar(int c, char *re, char *text)
{
do{ // a * matches zero or more instances
if(matchhere(re, text))
return 1;
}while(*text!='\0' && (*text++==c || c=='.'));
return 0;
}

351
user/grind.c Normal file
View File

@@ -0,0 +1,351 @@
//
// run random system calls in parallel forever.
//
#include "kernel/param.h"
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
#include "kernel/fs.h"
#include "kernel/fcntl.h"
#include "kernel/syscall.h"
#include "kernel/memlayout.h"
#include "kernel/riscv.h"
// from FreeBSD.
int
do_rand(unsigned long *ctx)
{
/*
* Compute x = (7^5 * x) mod (2^31 - 1)
* without overflowing 31 bits:
* (2^31 - 1) = 127773 * (7^5) + 2836
* From "Random number generators: good ones are hard to find",
* Park and Miller, Communications of the ACM, vol. 31, no. 10,
* October 1988, p. 1195.
*/
long hi, lo, x;
/* Transform to [1, 0x7ffffffe] range. */
x = (*ctx % 0x7ffffffe) + 1;
hi = x / 127773;
lo = x % 127773;
x = 16807 * lo - 2836 * hi;
if (x < 0)
x += 0x7fffffff;
/* Transform to [0, 0x7ffffffd] range. */
x--;
*ctx = x;
return (x);
}
unsigned long rand_next = 1;
int
rand(void)
{
return (do_rand(&rand_next));
}
void
go(int which_child)
{
int fd = -1;
static char buf[999];
char *break0 = sbrk(0);
uint64 iters = 0;
mkdir("grindir");
if(chdir("grindir") != 0){
printf("grind: chdir grindir failed\n");
exit(1);
}
chdir("/");
while(1){
iters++;
if((iters % 500) == 0)
write(1, which_child?"B":"A", 1);
int what = rand() % 23;
if(what == 1){
close(open("grindir/../a", O_CREATE|O_RDWR));
} else if(what == 2){
close(open("grindir/../grindir/../b", O_CREATE|O_RDWR));
} else if(what == 3){
unlink("grindir/../a");
} else if(what == 4){
if(chdir("grindir") != 0){
printf("grind: chdir grindir failed\n");
exit(1);
}
unlink("../b");
chdir("/");
} else if(what == 5){
close(fd);
fd = open("/grindir/../a", O_CREATE|O_RDWR);
} else if(what == 6){
close(fd);
fd = open("/./grindir/./../b", O_CREATE|O_RDWR);
} else if(what == 7){
write(fd, buf, sizeof(buf));
} else if(what == 8){
read(fd, buf, sizeof(buf));
} else if(what == 9){
mkdir("grindir/../a");
close(open("a/../a/./a", O_CREATE|O_RDWR));
unlink("a/a");
} else if(what == 10){
mkdir("/../b");
close(open("grindir/../b/b", O_CREATE|O_RDWR));
unlink("b/b");
} else if(what == 11){
unlink("b");
link("../grindir/./../a", "../b");
} else if(what == 12){
unlink("../grindir/../a");
link(".././b", "/grindir/../a");
} else if(what == 13){
int pid = fork();
if(pid == 0){
exit(0);
} else if(pid < 0){
printf("grind: fork failed\n");
exit(1);
}
wait(0);
} else if(what == 14){
int pid = fork();
if(pid == 0){
fork();
fork();
exit(0);
} else if(pid < 0){
printf("grind: fork failed\n");
exit(1);
}
wait(0);
} else if(what == 15){
sbrk(6011);
} else if(what == 16){
if(sbrk(0) > break0)
sbrk(-(sbrk(0) - break0));
} else if(what == 17){
int pid = fork();
if(pid == 0){
close(open("a", O_CREATE|O_RDWR));
exit(0);
} else if(pid < 0){
printf("grind: fork failed\n");
exit(1);
}
if(chdir("../grindir/..") != 0){
printf("grind: chdir failed\n");
exit(1);
}
kill(pid);
wait(0);
} else if(what == 18){
int pid = fork();
if(pid == 0){
kill(getpid());
exit(0);
} else if(pid < 0){
printf("grind: fork failed\n");
exit(1);
}
wait(0);
} else if(what == 19){
int fds[2];
if(pipe(fds) < 0){
printf("grind: pipe failed\n");
exit(1);
}
int pid = fork();
if(pid == 0){
fork();
fork();
if(write(fds[1], "x", 1) != 1)
printf("grind: pipe write failed\n");
char c;
if(read(fds[0], &c, 1) != 1)
printf("grind: pipe read failed\n");
exit(0);
} else if(pid < 0){
printf("grind: fork failed\n");
exit(1);
}
close(fds[0]);
close(fds[1]);
wait(0);
} else if(what == 20){
int pid = fork();
if(pid == 0){
unlink("a");
mkdir("a");
chdir("a");
unlink("../a");
fd = open("x", O_CREATE|O_RDWR);
unlink("x");
exit(0);
} else if(pid < 0){
printf("grind: fork failed\n");
exit(1);
}
wait(0);
} else if(what == 21){
unlink("c");
// should always succeed. check that there are free i-nodes,
// file descriptors, blocks.
int fd1 = open("c", O_CREATE|O_RDWR);
if(fd1 < 0){
printf("grind: create c failed\n");
exit(1);
}
if(write(fd1, "x", 1) != 1){
printf("grind: write c failed\n");
exit(1);
}
struct stat st;
if(fstat(fd1, &st) != 0){
printf("grind: fstat failed\n");
exit(1);
}
if(st.size != 1){
printf("grind: fstat reports wrong size %d\n", (int)st.size);
exit(1);
}
if(st.ino > 200){
printf("grind: fstat reports crazy i-number %d\n", st.ino);
exit(1);
}
close(fd1);
unlink("c");
} else if(what == 22){
// echo hi | cat
int aa[2], bb[2];
if(pipe(aa) < 0){
fprintf(2, "grind: pipe failed\n");
exit(1);
}
if(pipe(bb) < 0){
fprintf(2, "grind: pipe failed\n");
exit(1);
}
int pid1 = fork();
if(pid1 == 0){
close(bb[0]);
close(bb[1]);
close(aa[0]);
close(1);
if(dup(aa[1]) != 1){
fprintf(2, "grind: dup failed\n");
exit(1);
}
close(aa[1]);
char *args[3] = { "echo", "hi", 0 };
exec("grindir/../echo", args);
fprintf(2, "grind: echo: not found\n");
exit(2);
} else if(pid1 < 0){
fprintf(2, "grind: fork failed\n");
exit(3);
}
int pid2 = fork();
if(pid2 == 0){
close(aa[1]);
close(bb[0]);
close(0);
if(dup(aa[0]) != 0){
fprintf(2, "grind: dup failed\n");
exit(4);
}
close(aa[0]);
close(1);
if(dup(bb[1]) != 1){
fprintf(2, "grind: dup failed\n");
exit(5);
}
close(bb[1]);
char *args[2] = { "cat", 0 };
exec("/cat", args);
fprintf(2, "grind: cat: not found\n");
exit(6);
} else if(pid2 < 0){
fprintf(2, "grind: fork failed\n");
exit(7);
}
close(aa[0]);
close(aa[1]);
close(bb[1]);
char buf[4] = { 0, 0, 0, 0 };
read(bb[0], buf+0, 1);
read(bb[0], buf+1, 1);
read(bb[0], buf+2, 1);
close(bb[0]);
int st1, st2;
wait(&st1);
wait(&st2);
if(st1 != 0 || st2 != 0 || strcmp(buf, "hi\n") != 0){
printf("grind: exec pipeline failed %d %d \"%s\"\n", st1, st2, buf);
exit(1);
}
}
}
}
void
iter()
{
unlink("a");
unlink("b");
int pid1 = fork();
if(pid1 < 0){
printf("grind: fork failed\n");
exit(1);
}
if(pid1 == 0){
rand_next ^= 31;
go(0);
exit(0);
}
int pid2 = fork();
if(pid2 < 0){
printf("grind: fork failed\n");
exit(1);
}
if(pid2 == 0){
rand_next ^= 7177;
go(1);
exit(0);
}
int st1 = -1;
wait(&st1);
if(st1 != 0){
kill(pid1);
kill(pid2);
}
int st2 = -1;
wait(&st2);
exit(0);
}
int
main()
{
while(1){
int pid = fork();
if(pid == 0){
iter();
exit(0);
}
if(pid > 0){
wait(0);
}
sleep(20);
rand_next += 1;
}
}

54
user/init.c Normal file
View File

@@ -0,0 +1,54 @@
// init: The initial user-level program
#include "kernel/types.h"
#include "kernel/stat.h"
#include "kernel/spinlock.h"
#include "kernel/sleeplock.h"
#include "kernel/fs.h"
#include "kernel/file.h"
#include "user/user.h"
#include "kernel/fcntl.h"
char *argv[] = { "sh", 0 };
int
main(void)
{
int pid, wpid;
if(open("console", O_RDWR) < 0){
mknod("console", CONSOLE, 0);
open("console", O_RDWR);
}
dup(0); // stdout
dup(0); // stderr
for(;;){
printf("init: starting sh\n");
pid = fork();
if(pid < 0){
printf("init: fork failed\n");
exit(1);
}
if(pid == 0){
exec("sh", argv);
printf("init: exec sh failed\n");
exit(1);
}
for(;;){
// this call to wait() returns if the shell exits,
// or if a parentless process exits.
wpid = wait((int *) 0);
if(wpid == pid){
// the shell exited; restart it.
break;
} else if(wpid < 0){
printf("init: wait returned an error\n");
exit(1);
} else {
// it was a parentless process; do nothing.
}
}
}
}

28
user/initcode.S Normal file
View File

@@ -0,0 +1,28 @@
# Initial process that execs /init.
# This code runs in user space.
#include "syscall.h"
# exec(init, argv)
.globl start
start:
la a0, init
la a1, argv
li a7, SYS_exec
ecall
# for(;;) exit();
exit:
li a7, SYS_exit
ecall
jal exit
# char init[] = "/init\0";
init:
.string "/init\0"
# char *argv[] = { init, 0 };
.p2align 2
argv:
.long init
.long 0

17
user/kill.c Normal file
View File

@@ -0,0 +1,17 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
int
main(int argc, char **argv)
{
int i;
if(argc < 2){
fprintf(2, "usage: kill pid...\n");
exit(1);
}
for(i=1; i<argc; i++)
kill(atoi(argv[i]));
exit(0);
}

15
user/ln.c Normal file
View File

@@ -0,0 +1,15 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
int
main(int argc, char *argv[])
{
if(argc != 3){
fprintf(2, "Usage: ln old new\n");
exit(1);
}
if(link(argv[1], argv[2]) < 0)
fprintf(2, "link %s %s: failed\n", argv[1], argv[2]);
exit(0);
}

87
user/ls.c Normal file
View File

@@ -0,0 +1,87 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
#include "kernel/fs.h"
#include "kernel/fcntl.h"
char*
fmtname(char *path)
{
static char buf[DIRSIZ+1];
char *p;
// Find first character after last slash.
for(p=path+strlen(path); p >= path && *p != '/'; p--)
;
p++;
// Return blank-padded name.
if(strlen(p) >= DIRSIZ)
return p;
memmove(buf, p, strlen(p));
memset(buf+strlen(p), ' ', DIRSIZ-strlen(p));
return buf;
}
void
ls(char *path)
{
char buf[512], *p;
int fd;
struct dirent de;
struct stat st;
if((fd = open(path, O_RDONLY)) < 0){
fprintf(2, "ls: cannot open %s\n", path);
return;
}
if(fstat(fd, &st) < 0){
fprintf(2, "ls: cannot stat %s\n", path);
close(fd);
return;
}
switch(st.type){
case T_DEVICE:
case T_FILE:
printf("%s %d %d %l\n", fmtname(path), st.type, st.ino, st.size);
break;
case T_DIR:
if(strlen(path) + 1 + DIRSIZ + 1 > sizeof buf){
printf("ls: path too long\n");
break;
}
strcpy(buf, path);
p = buf+strlen(buf);
*p++ = '/';
while(read(fd, &de, sizeof(de)) == sizeof(de)){
if(de.inum == 0)
continue;
memmove(p, de.name, DIRSIZ);
p[DIRSIZ] = 0;
if(stat(buf, &st) < 0){
printf("ls: cannot stat %s\n", buf);
continue;
}
printf("%s %d %d %d\n", fmtname(buf), st.type, st.ino, st.size);
}
break;
}
close(fd);
}
int
main(int argc, char *argv[])
{
int i;
if(argc < 2){
ls(".");
exit(0);
}
for(i=1; i<argc; i++)
ls(argv[i]);
exit(0);
}

23
user/mkdir.c Normal file
View File

@@ -0,0 +1,23 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
int
main(int argc, char *argv[])
{
int i;
if(argc < 2){
fprintf(2, "Usage: mkdir files...\n");
exit(1);
}
for(i = 1; i < argc; i++){
if(mkdir(argv[i]) < 0){
fprintf(2, "mkdir: %s failed to create\n", argv[i]);
break;
}
}
exit(0);
}

113
user/printf.c Normal file
View File

@@ -0,0 +1,113 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
#include <stdarg.h>
static char digits[] = "0123456789ABCDEF";
static void
putc(int fd, char c)
{
write(fd, &c, 1);
}
static void
printint(int fd, int xx, int base, int sgn)
{
char buf[16];
int i, neg;
uint x;
neg = 0;
if(sgn && xx < 0){
neg = 1;
x = -xx;
} else {
x = xx;
}
i = 0;
do{
buf[i++] = digits[x % base];
}while((x /= base) != 0);
if(neg)
buf[i++] = '-';
while(--i >= 0)
putc(fd, buf[i]);
}
static void
printptr(int fd, uint64 x) {
int i;
putc(fd, '0');
putc(fd, 'x');
for (i = 0; i < (sizeof(uint64) * 2); i++, x <<= 4)
putc(fd, digits[x >> (sizeof(uint64) * 8 - 4)]);
}
// Print to the given fd. Only understands %d, %x, %p, %s.
void
vprintf(int fd, const char *fmt, va_list ap)
{
char *s;
int c, i, state;
state = 0;
for(i = 0; fmt[i]; i++){
c = fmt[i] & 0xff;
if(state == 0){
if(c == '%'){
state = '%';
} else {
putc(fd, c);
}
} else if(state == '%'){
if(c == 'd'){
printint(fd, va_arg(ap, int), 10, 1);
} else if(c == 'l') {
printint(fd, va_arg(ap, uint64), 10, 0);
} else if(c == 'x') {
printint(fd, va_arg(ap, int), 16, 0);
} else if(c == 'p') {
printptr(fd, va_arg(ap, uint64));
} else if(c == 's'){
s = va_arg(ap, char*);
if(s == 0)
s = "(null)";
while(*s != 0){
putc(fd, *s);
s++;
}
} else if(c == 'c'){
putc(fd, va_arg(ap, uint));
} else if(c == '%'){
putc(fd, c);
} else {
// Unknown % sequence. Print it to draw attention.
putc(fd, '%');
putc(fd, c);
}
state = 0;
}
}
}
void
fprintf(int fd, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vprintf(fd, fmt, ap);
}
void
printf(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vprintf(1, fmt, ap);
}

23
user/rm.c Normal file
View File

@@ -0,0 +1,23 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
int
main(int argc, char *argv[])
{
int i;
if(argc < 2){
fprintf(2, "Usage: rm files...\n");
exit(1);
}
for(i = 1; i < argc; i++){
if(unlink(argv[i]) < 0){
fprintf(2, "rm: %s failed to delete\n", argv[i]);
break;
}
}
exit(0);
}

494
user/sh.c Normal file
View File

@@ -0,0 +1,494 @@
// Shell.
#include "kernel/types.h"
#include "user/user.h"
#include "kernel/fcntl.h"
// Parsed command representation
#define EXEC 1
#define REDIR 2
#define PIPE 3
#define LIST 4
#define BACK 5
#define MAXARGS 10
struct cmd {
int type;
};
struct execcmd {
int type;
char *argv[MAXARGS];
char *eargv[MAXARGS];
};
struct redircmd {
int type;
struct cmd *cmd;
char *file;
char *efile;
int mode;
int fd;
};
struct pipecmd {
int type;
struct cmd *left;
struct cmd *right;
};
struct listcmd {
int type;
struct cmd *left;
struct cmd *right;
};
struct backcmd {
int type;
struct cmd *cmd;
};
int fork1(void); // Fork but panics on failure.
void panic(char*);
struct cmd *parsecmd(char*);
void runcmd(struct cmd*) __attribute__((noreturn));
// Execute cmd. Never returns.
void
runcmd(struct cmd *cmd)
{
int p[2];
struct backcmd *bcmd;
struct execcmd *ecmd;
struct listcmd *lcmd;
struct pipecmd *pcmd;
struct redircmd *rcmd;
if(cmd == 0)
exit(1);
switch(cmd->type){
default:
panic("runcmd");
case EXEC:
ecmd = (struct execcmd*)cmd;
if(ecmd->argv[0] == 0)
exit(1);
exec(ecmd->argv[0], ecmd->argv);
fprintf(2, "exec %s failed\n", ecmd->argv[0]);
break;
case REDIR:
rcmd = (struct redircmd*)cmd;
close(rcmd->fd);
if(open(rcmd->file, rcmd->mode) < 0){
fprintf(2, "open %s failed\n", rcmd->file);
exit(1);
}
runcmd(rcmd->cmd);
break;
case LIST:
lcmd = (struct listcmd*)cmd;
if(fork1() == 0)
runcmd(lcmd->left);
wait(0);
runcmd(lcmd->right);
break;
case PIPE:
pcmd = (struct pipecmd*)cmd;
if(pipe(p) < 0)
panic("pipe");
if(fork1() == 0){
close(1);
dup(p[1]);
close(p[0]);
close(p[1]);
runcmd(pcmd->left);
}
if(fork1() == 0){
close(0);
dup(p[0]);
close(p[0]);
close(p[1]);
runcmd(pcmd->right);
}
close(p[0]);
close(p[1]);
wait(0);
wait(0);
break;
case BACK:
bcmd = (struct backcmd*)cmd;
if(fork1() == 0)
runcmd(bcmd->cmd);
break;
}
exit(0);
}
int
getcmd(char *buf, int nbuf)
{
write(2, "$ ", 2);
memset(buf, 0, nbuf);
gets(buf, nbuf);
if(buf[0] == 0) // EOF
return -1;
return 0;
}
int
main(void)
{
static char buf[100];
int fd;
// Ensure that three file descriptors are open.
while((fd = open("console", O_RDWR)) >= 0){
if(fd >= 3){
close(fd);
break;
}
}
// Read and run input commands.
while(getcmd(buf, sizeof(buf)) >= 0){
if(buf[0] == 'c' && buf[1] == 'd' && buf[2] == ' '){
// Chdir must be called by the parent, not the child.
buf[strlen(buf)-1] = 0; // chop \n
if(chdir(buf+3) < 0)
fprintf(2, "cannot cd %s\n", buf+3);
continue;
}
if(fork1() == 0)
runcmd(parsecmd(buf));
wait(0);
}
exit(0);
}
void
panic(char *s)
{
fprintf(2, "%s\n", s);
exit(1);
}
int
fork1(void)
{
int pid;
pid = fork();
if(pid == -1)
panic("fork");
return pid;
}
//PAGEBREAK!
// Constructors
struct cmd*
execcmd(void)
{
struct execcmd *cmd;
cmd = malloc(sizeof(*cmd));
memset(cmd, 0, sizeof(*cmd));
cmd->type = EXEC;
return (struct cmd*)cmd;
}
struct cmd*
redircmd(struct cmd *subcmd, char *file, char *efile, int mode, int fd)
{
struct redircmd *cmd;
cmd = malloc(sizeof(*cmd));
memset(cmd, 0, sizeof(*cmd));
cmd->type = REDIR;
cmd->cmd = subcmd;
cmd->file = file;
cmd->efile = efile;
cmd->mode = mode;
cmd->fd = fd;
return (struct cmd*)cmd;
}
struct cmd*
pipecmd(struct cmd *left, struct cmd *right)
{
struct pipecmd *cmd;
cmd = malloc(sizeof(*cmd));
memset(cmd, 0, sizeof(*cmd));
cmd->type = PIPE;
cmd->left = left;
cmd->right = right;
return (struct cmd*)cmd;
}
struct cmd*
listcmd(struct cmd *left, struct cmd *right)
{
struct listcmd *cmd;
cmd = malloc(sizeof(*cmd));
memset(cmd, 0, sizeof(*cmd));
cmd->type = LIST;
cmd->left = left;
cmd->right = right;
return (struct cmd*)cmd;
}
struct cmd*
backcmd(struct cmd *subcmd)
{
struct backcmd *cmd;
cmd = malloc(sizeof(*cmd));
memset(cmd, 0, sizeof(*cmd));
cmd->type = BACK;
cmd->cmd = subcmd;
return (struct cmd*)cmd;
}
//PAGEBREAK!
// Parsing
char whitespace[] = " \t\r\n\v";
char symbols[] = "<|>&;()";
int
gettoken(char **ps, char *es, char **q, char **eq)
{
char *s;
int ret;
s = *ps;
while(s < es && strchr(whitespace, *s))
s++;
if(q)
*q = s;
ret = *s;
switch(*s){
case 0:
break;
case '|':
case '(':
case ')':
case ';':
case '&':
case '<':
s++;
break;
case '>':
s++;
if(*s == '>'){
ret = '+';
s++;
}
break;
default:
ret = 'a';
while(s < es && !strchr(whitespace, *s) && !strchr(symbols, *s))
s++;
break;
}
if(eq)
*eq = s;
while(s < es && strchr(whitespace, *s))
s++;
*ps = s;
return ret;
}
int
peek(char **ps, char *es, char *toks)
{
char *s;
s = *ps;
while(s < es && strchr(whitespace, *s))
s++;
*ps = s;
return *s && strchr(toks, *s);
}
struct cmd *parseline(char**, char*);
struct cmd *parsepipe(char**, char*);
struct cmd *parseexec(char**, char*);
struct cmd *nulterminate(struct cmd*);
struct cmd*
parsecmd(char *s)
{
char *es;
struct cmd *cmd;
es = s + strlen(s);
cmd = parseline(&s, es);
peek(&s, es, "");
if(s != es){
fprintf(2, "leftovers: %s\n", s);
panic("syntax");
}
nulterminate(cmd);
return cmd;
}
struct cmd*
parseline(char **ps, char *es)
{
struct cmd *cmd;
cmd = parsepipe(ps, es);
while(peek(ps, es, "&")){
gettoken(ps, es, 0, 0);
cmd = backcmd(cmd);
}
if(peek(ps, es, ";")){
gettoken(ps, es, 0, 0);
cmd = listcmd(cmd, parseline(ps, es));
}
return cmd;
}
struct cmd*
parsepipe(char **ps, char *es)
{
struct cmd *cmd;
cmd = parseexec(ps, es);
if(peek(ps, es, "|")){
gettoken(ps, es, 0, 0);
cmd = pipecmd(cmd, parsepipe(ps, es));
}
return cmd;
}
struct cmd*
parseredirs(struct cmd *cmd, char **ps, char *es)
{
int tok;
char *q, *eq;
while(peek(ps, es, "<>")){
tok = gettoken(ps, es, 0, 0);
if(gettoken(ps, es, &q, &eq) != 'a')
panic("missing file for redirection");
switch(tok){
case '<':
cmd = redircmd(cmd, q, eq, O_RDONLY, 0);
break;
case '>':
cmd = redircmd(cmd, q, eq, O_WRONLY|O_CREATE|O_TRUNC, 1);
break;
case '+': // >>
cmd = redircmd(cmd, q, eq, O_WRONLY|O_CREATE, 1);
break;
}
}
return cmd;
}
struct cmd*
parseblock(char **ps, char *es)
{
struct cmd *cmd;
if(!peek(ps, es, "("))
panic("parseblock");
gettoken(ps, es, 0, 0);
cmd = parseline(ps, es);
if(!peek(ps, es, ")"))
panic("syntax - missing )");
gettoken(ps, es, 0, 0);
cmd = parseredirs(cmd, ps, es);
return cmd;
}
struct cmd*
parseexec(char **ps, char *es)
{
char *q, *eq;
int tok, argc;
struct execcmd *cmd;
struct cmd *ret;
if(peek(ps, es, "("))
return parseblock(ps, es);
ret = execcmd();
cmd = (struct execcmd*)ret;
argc = 0;
ret = parseredirs(ret, ps, es);
while(!peek(ps, es, "|)&;")){
if((tok=gettoken(ps, es, &q, &eq)) == 0)
break;
if(tok != 'a')
panic("syntax");
cmd->argv[argc] = q;
cmd->eargv[argc] = eq;
argc++;
if(argc >= MAXARGS)
panic("too many args");
ret = parseredirs(ret, ps, es);
}
cmd->argv[argc] = 0;
cmd->eargv[argc] = 0;
return ret;
}
// NUL-terminate all the counted strings.
struct cmd*
nulterminate(struct cmd *cmd)
{
int i;
struct backcmd *bcmd;
struct execcmd *ecmd;
struct listcmd *lcmd;
struct pipecmd *pcmd;
struct redircmd *rcmd;
if(cmd == 0)
return 0;
switch(cmd->type){
case EXEC:
ecmd = (struct execcmd*)cmd;
for(i=0; ecmd->argv[i]; i++)
*ecmd->eargv[i] = 0;
break;
case REDIR:
rcmd = (struct redircmd*)cmd;
nulterminate(rcmd->cmd);
*rcmd->efile = 0;
break;
case PIPE:
pcmd = (struct pipecmd*)cmd;
nulterminate(pcmd->left);
nulterminate(pcmd->right);
break;
case LIST:
lcmd = (struct listcmd*)cmd;
nulterminate(lcmd->left);
nulterminate(lcmd->right);
break;
case BACK:
bcmd = (struct backcmd*)cmd;
nulterminate(bcmd->cmd);
break;
}
return cmd;
}

0
user/sleep.c Normal file
View File

49
user/stressfs.c Normal file
View File

@@ -0,0 +1,49 @@
// Demonstrate that moving the "acquire" in iderw after the loop that
// appends to the idequeue results in a race.
// For this to work, you should also add a spin within iderw's
// idequeue traversal loop. Adding the following demonstrated a panic
// after about 5 runs of stressfs in QEMU on a 2.1GHz CPU:
// for (i = 0; i < 40000; i++)
// asm volatile("");
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
#include "kernel/fs.h"
#include "kernel/fcntl.h"
int
main(int argc, char *argv[])
{
int fd, i;
char path[] = "stressfs0";
char data[512];
printf("stressfs starting\n");
memset(data, 'a', sizeof(data));
for(i = 0; i < 4; i++)
if(fork() > 0)
break;
printf("write %d\n", i);
path[8] += i;
fd = open(path, O_CREATE | O_RDWR);
for(i = 0; i < 20; i++)
// printf(fd, "%d\n", i);
write(fd, data, sizeof(data));
close(fd);
printf("read\n");
fd = open(path, O_RDONLY);
for (i = 0; i < 20; i++)
read(fd, data, sizeof(data));
close(fd);
wait(0);
exit(0);
}

147
user/ulib.c Normal file
View File

@@ -0,0 +1,147 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "kernel/fcntl.h"
#include "user/user.h"
//
// wrapper so that it's OK if main() does not call exit().
//
void
_main()
{
extern int main();
main();
exit(0);
}
char*
strcpy(char *s, const char *t)
{
char *os;
os = s;
while((*s++ = *t++) != 0)
;
return os;
}
int
strcmp(const char *p, const char *q)
{
while(*p && *p == *q)
p++, q++;
return (uchar)*p - (uchar)*q;
}
uint
strlen(const char *s)
{
int n;
for(n = 0; s[n]; n++)
;
return n;
}
void*
memset(void *dst, int c, uint n)
{
char *cdst = (char *) dst;
int i;
for(i = 0; i < n; i++){
cdst[i] = c;
}
return dst;
}
char*
strchr(const char *s, char c)
{
for(; *s; s++)
if(*s == c)
return (char*)s;
return 0;
}
char*
gets(char *buf, int max)
{
int i, cc;
char c;
for(i=0; i+1 < max; ){
cc = read(0, &c, 1);
if(cc < 1)
break;
buf[i++] = c;
if(c == '\n' || c == '\r')
break;
}
buf[i] = '\0';
return buf;
}
int
stat(const char *n, struct stat *st)
{
int fd;
int r;
fd = open(n, O_RDONLY);
if(fd < 0)
return -1;
r = fstat(fd, st);
close(fd);
return r;
}
int
atoi(const char *s)
{
int n;
n = 0;
while('0' <= *s && *s <= '9')
n = n*10 + *s++ - '0';
return n;
}
void*
memmove(void *vdst, const void *vsrc, int n)
{
char *dst;
const char *src;
dst = vdst;
src = vsrc;
if (src > dst) {
while(n-- > 0)
*dst++ = *src++;
} else {
dst += n;
src += n;
while(n-- > 0)
*--dst = *--src;
}
return vdst;
}
int
memcmp(const void *s1, const void *s2, uint n)
{
const char *p1 = s1, *p2 = s2;
while (n-- > 0) {
if (*p1 != *p2) {
return *p1 - *p2;
}
p1++;
p2++;
}
return 0;
}
void *
memcpy(void *dst, const void *src, uint n)
{
return memmove(dst, src, n);
}

90
user/umalloc.c Normal file
View File

@@ -0,0 +1,90 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
#include "kernel/param.h"
// Memory allocator by Kernighan and Ritchie,
// The C programming Language, 2nd ed. Section 8.7.
typedef long Align;
union header {
struct {
union header *ptr;
uint size;
} s;
Align x;
};
typedef union header Header;
static Header base;
static Header *freep;
void
free(void *ap)
{
Header *bp, *p;
bp = (Header*)ap - 1;
for(p = freep; !(bp > p && bp < p->s.ptr); p = p->s.ptr)
if(p >= p->s.ptr && (bp > p || bp < p->s.ptr))
break;
if(bp + bp->s.size == p->s.ptr){
bp->s.size += p->s.ptr->s.size;
bp->s.ptr = p->s.ptr->s.ptr;
} else
bp->s.ptr = p->s.ptr;
if(p + p->s.size == bp){
p->s.size += bp->s.size;
p->s.ptr = bp->s.ptr;
} else
p->s.ptr = bp;
freep = p;
}
static Header*
morecore(uint nu)
{
char *p;
Header *hp;
if(nu < 4096)
nu = 4096;
p = sbrk(nu * sizeof(Header));
if(p == (char*)-1)
return 0;
hp = (Header*)p;
hp->s.size = nu;
free((void*)(hp + 1));
return freep;
}
void*
malloc(uint nbytes)
{
Header *p, *prevp;
uint nunits;
nunits = (nbytes + sizeof(Header) - 1)/sizeof(Header) + 1;
if((prevp = freep) == 0){
base.s.ptr = freep = prevp = &base;
base.s.size = 0;
}
for(p = prevp->s.ptr; ; prevp = p, p = p->s.ptr){
if(p->s.size >= nunits){
if(p->s.size == nunits)
prevp->s.ptr = p->s.ptr;
else {
p->s.size -= nunits;
p += p->s.size;
p->s.size = nunits;
}
freep = prevp;
return (void*)(p + 1);
}
if(p == freep)
if((p = morecore(nunits)) == 0)
return 0;
}
}

41
user/user.h Normal file
View File

@@ -0,0 +1,41 @@
struct stat;
// system calls
int fork(void);
int exit(int) __attribute__((noreturn));
int wait(int*);
int pipe(int*);
int write(int, const void*, int);
int read(int, void*, int);
int close(int);
int kill(int);
int exec(const char*, char**);
int open(const char*, int);
int mknod(const char*, short, short);
int unlink(const char*);
int fstat(int fd, struct stat*);
int link(const char*, const char*);
int mkdir(const char*);
int chdir(const char*);
int dup(int);
int getpid(void);
char* sbrk(int);
int sleep(int);
int uptime(void);
// ulib.c
int stat(const char*, struct stat*);
char* strcpy(char*, const char*);
void *memmove(void*, const void*, int);
char* strchr(const char*, char c);
int strcmp(const char*, const char*);
void fprintf(int, const char*, ...);
void printf(const char*, ...);
char* gets(char*, int max);
uint strlen(const char*);
void* memset(void*, int, uint);
void* malloc(uint);
void free(void*);
int atoi(const char*);
int memcmp(const void *, const void *, uint);
void *memcpy(void *, const void *, uint);

36
user/user.ld Normal file
View File

@@ -0,0 +1,36 @@
OUTPUT_ARCH( "riscv" )
ENTRY( _main )
SECTIONS
{
. = 0x0;
.text : {
*(.text .text.*)
}
.rodata : {
. = ALIGN(16);
*(.srodata .srodata.*) /* do not need to distinguish this from .rodata */
. = ALIGN(16);
*(.rodata .rodata.*)
. = ALIGN(0x1000);
}
.data : {
. = ALIGN(16);
*(.sdata .sdata.*) /* do not need to distinguish this from .data */
. = ALIGN(16);
*(.data .data.*)
}
.bss : {
. = ALIGN(16);
*(.sbss .sbss.*) /* do not need to distinguish this from .bss */
. = ALIGN(16);
*(.bss .bss.*)
}
PROVIDE(end = .);
}

3103
user/usertests.c Normal file

File diff suppressed because it is too large Load Diff

38
user/usys.pl Executable file
View File

@@ -0,0 +1,38 @@
#!/usr/bin/perl -w
# Generate usys.S, the stubs for syscalls.
print "# generated by usys.pl - do not edit\n";
print "#include \"kernel/syscall.h\"\n";
sub entry {
my $name = shift;
print ".global $name\n";
print "${name}:\n";
print " li a7, SYS_${name}\n";
print " ecall\n";
print " ret\n";
}
entry("fork");
entry("exit");
entry("wait");
entry("pipe");
entry("read");
entry("write");
entry("close");
entry("kill");
entry("exec");
entry("open");
entry("mknod");
entry("unlink");
entry("fstat");
entry("link");
entry("mkdir");
entry("chdir");
entry("dup");
entry("getpid");
entry("sbrk");
entry("sleep");
entry("uptime");

55
user/wc.c Normal file
View File

@@ -0,0 +1,55 @@
#include "kernel/types.h"
#include "kernel/stat.h"
#include "kernel/fcntl.h"
#include "user/user.h"
char buf[512];
void
wc(int fd, char *name)
{
int i, n;
int l, w, c, inword;
l = w = c = 0;
inword = 0;
while((n = read(fd, buf, sizeof(buf))) > 0){
for(i=0; i<n; i++){
c++;
if(buf[i] == '\n')
l++;
if(strchr(" \r\t\n\v", buf[i]))
inword = 0;
else if(!inword){
w++;
inword = 1;
}
}
}
if(n < 0){
printf("wc: read error\n");
exit(1);
}
printf("%d %d %d %s\n", l, w, c, name);
}
int
main(int argc, char *argv[])
{
int fd, i;
if(argc <= 1){
wc(0, "");
exit(0);
}
for(i = 1; i < argc; i++){
if((fd = open(argv[i], O_RDONLY)) < 0){
printf("wc: cannot open %s\n", argv[i]);
exit(1);
}
wc(fd, argv[i]);
close(fd);
}
exit(0);
}

6
user/xargstest.sh Normal file
View File

@@ -0,0 +1,6 @@
mkdir a
echo hello > a/b
mkdir c
echo hello > c/b
echo hello > b
find . b | xargs grep hello

14
user/zombie.c Normal file
View File

@@ -0,0 +1,14 @@
// Create a zombie process that
// must be reparented at exit.
#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"
int
main(void)
{
if(fork() > 0)
sleep(5); // Let child exit before parent.
exit(0);
}