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#include <ctype.h> | |
#include <fcntl.h> | |
#include <linux/openat2.h> | |
#include <netinet/in.h> | |
#include <signal.h> | |
#include <stdlib.h> | |
#include <string.h> | |
#include <sys/socket.h> | |
#include <sys/syscall.h> | |
#include <unistd.h> | |
int main(int argc, char *argv[]) { | |
if (argc > 2) if (chdir(argv[2])) return 1; | |
int listenfd = socket(AF_INET, SOCK_STREAM, 0); | |
struct sockaddr_in sock = { | |
.sin_family = AF_INET, | |
.sin_port = htons(argc > 1 ? atoi(argv[1]) : 80), | |
}; | |
setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &(int){1}, sizeof(int)); | |
bind(listenfd, (struct sockaddr*)&sock, sizeof(sock)); | |
listen(listenfd, 10); | |
signal(SIGCHLD, SIG_IGN); | |
while (1) { | |
int fd = accept(listenfd, 0, 0); | |
setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &(struct timeval){ .tv_sec = 10 }, sizeof(struct timeval)); | |
if (!fork()) { | |
static char buf[4096]; | |
read(fd, buf, sizeof buf - 1); | |
if (strchr(buf, '\n')) *strchr(buf, '\n') = 0; | |
if (strchr(buf, '\r')) *strchr(buf, '\r') = 0; | |
if (strrchr(buf, ' ')) *strrchr(buf, ' ') = 0; | |
if (!strncmp(buf, "GET ", 4) || !strncmp(buf, "HEAD ", 5)) { | |
char *path = buf + 5 + (buf[0] == 'H'), *rptr = path, *wptr = path; | |
for ( ; *rptr; rptr++) { | |
if (*rptr != '%') *wptr++ = *rptr; | |
else if (isxdigit(rptr[1]) && isxdigit(rptr[2])) { | |
#define fromhex(x) (x >= '0' && x <= '9' ? x - '0' : (x|32) - 'a' + 10) | |
*wptr++ = (fromhex(rptr[1]) << 4) | fromhex(rptr[2]); | |
rptr += 2; | |
} | |
else { /* no */ } | |
} | |
*wptr = 0; | |
struct open_how how = { | |
.flags = O_RDONLY, | |
.resolve = RESOLVE_BENEATH, | |
}; | |
int f = syscall(SYS_openat2, AT_FDCWD, path, &how, sizeof how); | |
if (f < 0) write(fd, "HTTP/1.0 404 Not Found\r\n\r\n", 26); | |
else write(fd, "HTTP/1.0 200 OK\r\n\r\n", 19); | |
if (buf[0] == 'G') for (long l; (l = read(f, buf, sizeof buf)) > 0; ) write(fd, buf, l); | |
} | |
else write(fd, "HTTP/1.0 501 Not Implemented\r\n\r\n", 32); | |
break; | |
} | |
close(fd); | |
} | |
} |
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