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提交 5a97613b 创建 作者: Austin Clements's avatar Austin Clements
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Fit exec on a page. Again

上级 4e015d81
隐藏空白字符变更
内嵌 并排
正在显示 包含 2 行增加 和 5 行删除
exec.c
浏览文件 @ 5a97613b
...@@ -50,8 +50,7 @@ exec(char *path, char **argv) ...@@ -50,8 +50,7 @@ exec(char *path, char **argv)
ip = 0; ip = 0;
// Allocate two pages at the next page boundary. // Allocate two pages at the next page boundary.
// Make the first inaccessible. // Make the first inaccessible. Use the second as the user stack.
// Use the second as the user stack.
sz = PGROUNDUP(sz); sz = PGROUNDUP(sz);
if((sz = allocuvm(pgdir, sz, sz + 2*PGSIZE)) == 0) if((sz = allocuvm(pgdir, sz, sz + 2*PGSIZE)) == 0)
goto bad; goto bad;
...@@ -62,8 +61,7 @@ exec(char *path, char **argv) ...@@ -62,8 +61,7 @@ exec(char *path, char **argv)
for(argc = 0; argv[argc]; argc++) { for(argc = 0; argv[argc]; argc++) {
if(argc >= MAXARG) if(argc >= MAXARG)
goto bad; goto bad;
sp -= strlen(argv[argc]) + 1; sp = (sp - strlen(argv[argc]) + 1) & ~3;
sp &= ~3;
if(copyout(pgdir, sp, argv[argc], strlen(argv[argc]) + 1) < 0) if(copyout(pgdir, sp, argv[argc], strlen(argv[argc]) + 1) < 0)
goto bad; goto bad;
ustack[3+argc] = sp; ustack[3+argc] = sp;
...@@ -92,7 +90,6 @@ exec(char *path, char **argv) ...@@ -92,7 +90,6 @@ exec(char *path, char **argv)
proc->tf->esp = sp; proc->tf->esp = sp;
switchuvm(proc); switchuvm(proc);
freevm(oldpgdir); freevm(oldpgdir);
return 0; return 0;
bad: bad:
......
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