From 910b69f6b2c8243cd75cd13bb24af0a1b017d20b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89rico=20Nogueira?= <erico.erc@gmail.com>
Date: Fri, 21 May 2021 02:23:56 -0300
Subject: [PATCH] Respect that HTTP headers are case insensitive.

So we look for them using strcasestr instead fo strstr.

If this ever becomes a bottleneck, it can probably be optimized by only
trying to match the words right after "\r\n".
---
 files.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/files.c b/files.c
index cc18c79..c2863aa 100644
--- a/files.c
+++ b/files.c
@@ -1,3 +1,4 @@
+#define _GNU_SOURCE /* strcasestr */
 #include <stdlib.h>
 #include <unistd.h>
 #include <assert.h>
@@ -99,8 +100,8 @@ size_t ssl_to_mmap(struct transmission_information ti)
 
             if (ti.type == HTTP_CONN) {
                 // http headers need to be parsed for content length
-                const char *needle = "Content-Length: ";
-                char *length = strstr(st.header, needle);
+                const char *needle = "content-length: ";
+                char *length = strcasestr(st.header, needle);
                 if (length == NULL) {
                     fputs("header didn't contain content-length field\n", stderr);
                     rv = 0;