Homework 16 & 17

1100012749

---

Homework 16

9.15

Request	Block size (decimal bytes)	Block header (hex)
malloc(3)	8	0x9
malloc(11)	16	0x11
malloc(20)	24	0x19
malloc(21)	32	0x21

9.16

都是16

9.17

static char * cur = heap_listp; 
static void *find_fit(size_t asize) {
/* Next fit search */
    void *bp = cur;
    while(GET_ALLOC(HDRP(bp)) || GET_SIZE(HDRP(bp)) < asize) {
        bp = (GET_SIZE(HDRP(bp)) == 0) ? heap_listp : NEXT_BLKP(bp);
        if (bp == cur) return NULL;
    }
    cur = NEXT_BLKP(bp);
    return bp;
}

9.19

1. a
2. d
3. b

Homework 17

11.6

A.
void doit(int fd)中，sscanf(buf, "%s %s %s", method, uri, version);下加printf("%s %s %s\n", method, uri, version);
read_requesthdrs(rio_t *rp)按如下修改：

void read_requesthdrs(rio_t *rp) 
{
    char buf[MAXLINE];
    do{
        Rio_readlineb(rp, buf, MAXLINE);
        printf("%s", buf);
    }while(strcmp(buf, "\r\n"));
    return;
}

B.

GET / HTTP/1.1
Host: localhost:12345
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:32.0) Gecko/20100101 Firefox/32.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: keep-alive
Cache-Control: max-age=0

C. HTTP/1.1

D.
User-Agent: 标识生成请求的浏览器或其他客户程序
Accept: 浏览器或者其他客户程序能处理的MIME类型
Accept-Encoding: 可以接受的编码方案
Accept-Language: 可以接受的语言；

11.7

void get_filetype(char *filename, char *filetype) 
{
    if (strstr(filename, ".html"))
    strcpy(filetype, "text/html");
    else if (strstr(filename, ".gif"))
    strcpy(filetype, "image/gif");
    else if (strstr(filename, ".jpg"))
    strcpy(filetype, "image/jpeg");
    else if(strstr(filename, ".mpg") || strstr(filename, ".mp4"))
    strcpy(filetype, "video/mpeg"); 
    else
    strcpy(filetype, "text/plain");
}