Add HTTP/HTTPS Fetch() API to redbean

You can now say the following in your redbean Lua code:

    status,headers,payload = Fetch("https://foo.example")

The following Lua APIs have been introduced:

  - Fetch(str) → str,{str:str},str
  - GetHttpReason(int) → str
  - GetHttpReason(int) → str
  - ProgramSslFetchVerify(bool)
  - ProgramSslClientVerify(bool)

The following flags have been introduced:

  - `-j` enables client SSL verification
  - `-k` disables Fetch() SSL verification
  - `-t INT` may now be passed a negative value for keepalive

Lua exceptions now invoke Cosmopolitan's garbage collector when
unwinding the stack. So it's now safe to use _gc() w/ Lua 𝔱𝔥𝔯𝔬𝔴

See #97

net/http/http.h

@@ -36,6 +36,11 @@
 #define kHttpStateLf1     10
 #define kHttpStateLf2     11
 
+#define kHttpClientStateHeaders      0
+#define kHttpClientStateBody         1
+#define kHttpClientStateBodyChunked  2
+#define kHttpClientStateBodyLengthed 3
+
 #define kHttpStateChunkStart   0
 #define kHttpStateChunkSize    1
 #define kHttpStateChunkExt     2

net/http/http.mk

@@ -8,39 +8,22 @@ NET_HTTP = $(NET_HTTP_A_DEPS) $(NET_HTTP_A)
 NET_HTTP_A = o/$(MODE)/net/http/http.a
 NET_HTTP_A_FILES := $(wildcard net/http/*)
 NET_HTTP_A_HDRS = $(filter %.h,$(NET_HTTP_A_FILES))
-NET_HTTP_A_SRCS_S = $(filter %.S,$(NET_HTTP_A_FILES))
-NET_HTTP_A_SRCS_C = $(filter %.c,$(NET_HTTP_A_FILES))
-NET_HTTP_A_SRCS_R = $(filter %.rl,$(NET_HTTP_A_FILES))
-
-NET_HTTP_A_SRCS =				\
-	$(NET_HTTP_A_SRCS_S)			\
-	$(NET_HTTP_A_SRCS_C)			\
-	$(NET_HTTP_A_SRCS_R)
-
-NET_HTTP_A_OBJS =				\
-	$(NET_HTTP_A_SRCS_S:%.S=o/$(MODE)/%.o)	\
-	$(NET_HTTP_A_SRCS_C:%.c=o/$(MODE)/%.o)	\
-	$(NET_HTTP_A_SRCS_R:%.rl=o/$(MODE)/%.o)
+NET_HTTP_A_SRCS = $(filter %.c,$(NET_HTTP_A_FILES))
+NET_HTTP_A_OBJS = $(NET_HTTP_A_SRCS:%.c=o/$(MODE)/%.o)
 
 NET_HTTP_A_CHECKS =				\
 	$(NET_HTTP_A).pkg			\
 	$(NET_HTTP_A_HDRS:%=o/$(MODE)/%.ok)
 
 NET_HTTP_A_DIRECTDEPS =				\
-	LIBC_CALLS				\
 	LIBC_FMT				\
 	LIBC_INTRIN				\
-	LIBC_LOG				\
 	LIBC_MEM				\
 	LIBC_NEXGEN32E				\
-	LIBC_RUNTIME				\
-	LIBC_SOCK				\
-	LIBC_STDIO				\
 	LIBC_STR				\
 	LIBC_STUBS				\
 	LIBC_SYSV				\
-	LIBC_TIME				\
-	LIBC_X
+	LIBC_TIME
 
 NET_HTTP_A_DEPS :=				\
 	$(call uniq,$(foreach x,$(NET_HTTP_A_DIRECTDEPS),$($(x))))
@@ -76,10 +59,8 @@ o/$(MODE)/net/http/formathttpdatetime.o:	\
 NET_HTTP_LIBS = $(foreach x,$(NET_HTTP_ARTIFACTS),$($(x)))
 NET_HTTP_SRCS = $(foreach x,$(NET_HTTP_ARTIFACTS),$($(x)_SRCS))
 NET_HTTP_HDRS = $(foreach x,$(NET_HTTP_ARTIFACTS),$($(x)_HDRS))
-NET_HTTP_CHECKS = $(foreach x,$(NET_HTTP_ARTIFACTS),$($(x)_CHECKS))
 NET_HTTP_OBJS = $(foreach x,$(NET_HTTP_ARTIFACTS),$($(x)_OBJS))
+NET_HTTP_CHECKS = $(foreach x,$(NET_HTTP_ARTIFACTS),$($(x)_CHECKS))
 
 .PHONY: o/$(MODE)/net/http
-o/$(MODE)/net/http:				\
-		$(NET_HTTP_CHECKS)		\
-		$(NET_HTTP_A_SRCS_R:%.rl=%.svgz)
+o/$(MODE)/net/http: $(NET_HTTP_CHECKS)

net/http/isacceptablehost.c

@@ -16,6 +16,7 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/dns/dns.h"
 #include "libc/str/str.h"
 #include "net/http/http.h"
 
@@ -72,6 +73,7 @@ bool IsAcceptableHost(const char *s, size_t n) {
   int c, b, j;
   if (n == -1) n = s ? strlen(s) : 0;
   if (!n) return true;
+  if (n > DNS_NAME_MAX) return false;
   for (b = j = i = 0; i < n; ++i) {
     c = s[i] & 255;
     if (isdigit(c)) {

net/http/unchunk.c

@@ -43,7 +43,7 @@ ssize_t Unchunk(struct HttpUnchunker *u, char *p, size_t n, size_t *l) {
         if ((h = kHexToInt[c]) != -1) {
           u->m *= 16;
           u->m += h;
-          if (u->i + u->m >= n) return ebadmsg();
+          if (u->m >= 0x0000010000000000) return ebadmsg();
           break;
         }
         u->t = kHttpStateChunkExt;