Adds strstr and memmem. (#275)

Author: ncruces

sqlite3/libc/build.sh

@@ -23,14 +23,15 @@ EOF
 	-mbulk-memory -mreference-types \
 	-mnontrapping-fptoint -msign-ext \
 	-fno-stack-protector -fno-stack-clash-protection \
-	-Wl,-z,stack-size=1024 \
+	-Wl,-z,stack-size=4096 \
 	-Wl,--stack-first \
 	-Wl,--import-undefined \
 	-Wl,--initial-memory=16777216 \
 	-Wl,--export=memccpy \
 	-Wl,--export=memchr \
 	-Wl,--export=memcmp \
 	-Wl,--export=memcpy \
+	-Wl,--export=memmem \
 	-Wl,--export=memmove \
 	-Wl,--export=memrchr \
 	-Wl,--export=memset \
@@ -47,6 +48,7 @@ EOF
 	-Wl,--export=strncpy \
 	-Wl,--export=strrchr \
 	-Wl,--export=strspn \
+	-Wl,--export=strstr \
 	-Wl,--export=qsort
 
 "$BINARYEN/wasm-ctor-eval" -g -c _initialize libc.wasm -o libc.tmp