xv6安装包附带源码可供学习

#include "param.h" #include "types.h" #include "stat.h" #include "user.h" #include "fs.h" #include "fcntl.h" #include "syscall.h" #include "traps.h" #include "memlayout.h" char buf[8192]; char name[3]; char *echoargv[] = { "echo", "ALL", "TESTS", "PASSED", 0 }; int stdout = 1; // does chdir() call iput(p->cwd) in a transaction? void iputtest(void) { printf(stdout, "iput test\n"); if(mkdir("iputdir") < 0){ printf(stdout, "mkdir failed\n"); exit(); } if(chdir("iputdir") < 0){ printf(stdout, "chdir iputdir failed\n"); exit(); } if(unlink("../iputdir") < 0){ printf(stdout, "unlink ../iputdir failed\n"); exit(); } if(chdir("/") < 0){ printf(stdout, "chdir / failed\n"); exit(); } printf(stdout, "iput test ok\n"); } // does exit() call iput(p->cwd) in a transaction? void exitiputtest(void) { int pid; printf(stdout, "exitiput test\n"); pid = fork(); if(pid < 0){ printf(stdout, "fork failed\n"); exit(); } if(pid == 0){ if(mkdir("iputdir") < 0){ printf(stdout, "mkdir failed\n"); exit(); } if(chdir("iputdir") < 0){ printf(stdout, "child chdir failed\n"); exit(); } if(unlink("../iputdir") < 0){ printf(stdout, "unlink ../iputdir failed\n"); exit(); } exit(); } wait(); printf(stdout, "exitiput test ok\n"); } // does the error path in open() for attempt to write a // directory call iput() in a transaction? // needs a hacked kernel that pauses just after the namei() // call in sys_open(): // if((ip = namei(path)) == 0) // return -1; // { // int i; // for(i = 0; i < 10000; i++) // yield(); // } void openiputtest(void) { int pid; printf(stdout, "openiput test\n"); if(mkdir("oidir") < 0){ printf(stdout, "mkdir oidir failed\n"); exit(); } pid = fork(); if(pid < 0){ printf(stdout, "fork failed\n"); exit(); } if(pid == 0){ int fd = open("oidir", O_RDWR); if(fd >= 0){ printf(stdout, "open directory for write succeeded\n"); exit(); } exit(); } sleep(1); if(unlink("oidir") != 0){ printf(stdout, "unlink failed\n"); exit(); } wait(); printf(stdout, "openiput test ok\n"); } // simple file system tests void opentest(void) { int fd; printf(stdout, "open test\n"); fd = open("echo", 0); if(fd < 0){ printf(stdout, "open echo failed!\n"); exit(); } close(fd); fd = open("doesnotexist", 0); if(fd >= 0){ printf(stdout, "open doesnotexist succeeded!\n"); exit(); } printf(stdout, "open test ok\n"); } void writetest(void) { int fd; int i; printf(stdout, "small file test\n"); fd = open("small", O_CREATE|O_RDWR); if(fd >= 0){ printf(stdout, "creat small succeeded; ok\n"); } else { printf(stdout, "error: creat small failed!\n"); exit(); } for(i = 0; i < 100; i++){ if(write(fd, "aaaaaaaaaa", 10) != 10){ printf(stdout, "error: write aa %d new file failed\n", i); exit(); } if(write(fd, "bbbbbbbbbb", 10) != 10){ printf(stdout, "error: write bb %d new file failed\n", i); exit(); } } printf(stdout, "writes ok\n"); close(fd); fd = open("small", O_RDONLY); if(fd >= 0){ printf(stdout, "open small succeeded ok\n"); } else { printf(stdout, "error: open small failed!\n"); exit(); } i = read(fd, buf, 2000); if(i == 2000){ printf(stdout, "read succeeded ok\n"); } else { printf(stdout, "read failed\n"); exit(); } close(fd); if(unlink("small") < 0){ printf(stdout, "unlink small failed\n"); exit(); } printf(stdout, "small file test ok\n"); } void writetest1(void) { int i, fd, n; printf(stdout, "big files test\n"); fd = open("big", O_CREATE|O_RDWR); if(fd < 0){ printf(stdout, "error: creat big failed!\n"); exit(); } for(i = 0; i < MAXFILE; i++){ ((int*)buf)[0] = i; if(write(fd, buf, 512) != 512){ printf(stdout, "error: write big file failed\n", i); exit(); } } close(fd); fd = open("big", O_RDONLY); if(fd < 0){ printf(stdout, "error: open big failed!\n"); exit(); } n = 0; for(;;){ i = read(fd, buf, 512); if(i == 0){ if(n == MAXFILE - 1){ printf(stdout, "read only %d blocks from big", n); exit(); } break; } else if(i != 512){ printf(stdout, "read failed %d\n", i); exit(); } if(((int*)buf)[0] != n){ printf(stdout, "read content of block %d is %d\n", n, ((int*)buf)[0]); exit(); } n++; } close(fd); if(unlink("big") < 0){ printf(stdout, "unlink big failed\n"); exit(); } printf(stdout, "big files ok\n"); } void createtest(void) { int i, fd; printf(stdout, "many creates, followed by unlink test\n"); name[0] = 'a'; name[2] = '\0'; for(i = 0; i < 52; i++){ name[1] = '0' + i; fd = open(name, O_CREATE|O_RDWR); close(fd); } name[0] = 'a'; name[2] = '\0'; for(i = 0; i < 52; i++){ name[1] = '0' + i; unlink(name); } printf(stdout, "many creates, followed by unlink; ok\n"); } void dirtest(void) { printf(stdout, "mkdir test\n"); if(mkdir("dir0") < 0){ printf(stdout, "mkdir failed\n"); exit(); } if(chdir("dir0") < 0){ printf(stdout, "chdir dir0 failed\n"); exit(); } if(chdir("..") < 0){ printf(stdout, "chdir .. failed\n"); exit(); } if(unlink("dir0") < 0){ printf(stdout, "unlink dir0 failed\n"); exit(); } printf(stdout, "mkdir test ok\n"); } void exectest(void) { printf(stdout, "exec test\n"); if(exec("echo", echoargv) < 0){ printf(stdout, "exec echo failed\n"); exit(); } } // simple fork and pipe read/write void pipe1(void) { int fds[2], pid; int seq, i, n, cc, total; if(pipe(fds) != 0){ printf(1, "pipe() failed\n"); exit(); } pid = fork(); seq = 0; if(pid == 0){ close(fds[0]); for(n = 0; n < 5; n++){ for(i = 0; i < 1033; i++) buf[i] = seq++; if(write(fds[1], buf, 1033) != 1033){ printf(1, "pipe1 oops 1\n"); exit(); } } exit(); } else if(pid > 0){ close(fds[1]); total = 0; cc = 1; while((n = read(fds[0], buf, cc)) > 0){ for(i = 0; i < n; i++){ if((buf[i] & 0xff) != (seq++ & 0xff)){ printf(1, "pipe1 oops 2\n"); return; } } total += n; cc = cc * 2; if(cc > sizeof(buf)) cc = sizeof(buf); } if(total != 5 * 1033){ printf(1, "pipe1 oops 3 total %d\n", total); exit(); } close(fds[0]); wait(); } else { printf(1, "fork() failed\n"); exit(); } printf(1, "pipe1 ok\n"); } // meant to be run w/ at most two CPUs void preempt(void) { int pid1, pid2, pid3; int pfds[2]; printf(1, "preempt: "); pid1 = fork(); if(pid1 == 0) for(;;) ; pid2 = fork(); if(pid2 == 0) for(;;) ; pipe(pfds); pid3 = fork(); if(pid3 == 0){ close(pfds[0]); if(write(pfds[1], "x", 1) != 1) printf(1, "preempt write error"); close(pfds[1]); for(;;) ; } close(pfds[1]); if(read(pfds[0], buf, sizeof(buf)) != 1){ printf(1, "preempt read error"); return; } close(pfds[0]); printf(1, "kill... "); kill(pid1); kill(pid2); kill(pid3); printf(1, "wait... "); wait(); wait(); wait(); printf(1, "preempt ok\n"); } // try to find any races between exit and wait void exitwait(void) { int i, pid; for(i = 0; i < 100; i++){ pid = fork(); if(pid < 0){ printf(1, "fork failed\n"); return; } if(pid){ if(wait() != pid){ printf(1, "wait wrong pid\n"); return; } } else { exit(); } } printf(1, "exitwait ok\n"); } void mem(void) { void *m1, *m2; int pid, ppid; printf(1, "mem test\n"); ppid = getpid(); if((pid = fork()) == 0){ m1 = 0; while((m2 = malloc(10001