really fix netcat race

We hit this once every few Jenkins runs. This:

1. Ensures netcat has started before we try to use it.
2. Waits for it to actually write the request before trying to read it.

License: MIT
Signed-off-by: Steven Allen <steven@stebalien.com>

test/sharness/t0235-cli-request.sh

@@ -10,11 +10,31 @@ test_description="test http requests made by cli"
 
 test_init_ipfs
 
-test_expect_success "can make http request against nc server" '
-  nc -ld 5005 > nc_out &
+test_expect_success "start nc" '
+  rm -f nc_out nc_status nc_in && mkfifo nc_in nc_status
+  nc -v -l 127.0.0.1 5005 < nc_in > nc_out 2>nc_status &
   NCPID=$!
-  go-sleep 0.5s && kill "$NCPID" &
-  ipfs cat /ipfs/Qmabcdef --api /ip4/127.0.0.1/tcp/5005 || true
+
+  # Needed to "prime" nc
+  echo -n "" > nc_in
+
+  # Wait for it to start
+  head -1 nc_status
+'
+
+test_expect_success "can make http request against nc server" '
+  cat >nc_in <<EOF
+HTTP/1.1 200 OK
+Content-Type: text/plain
+Content-Length: 1
+
+.
+EOF
+ipfs cat /ipfs/Qmabcdef --api /ip4/127.0.0.1/tcp/5005
+'
+
+test_expect_success "wait for nc to exit" '
+  wait $NCPID
 '
 
 test_expect_success "output does not contain multipart info" '

test/sharness/t0236-cli-api-dns-resolve.sh

@@ -10,11 +10,31 @@ test_description="test dns resolution of api endpoint by cli"
 
 test_init_ipfs
 
-test_expect_success "can make http request against dns resolved nc server" '
-  nc -ld 5005 > nc_out &
+test_expect_success "start nc" '
+  rm -f nc_out nc_status nc_in && mkfifo nc_in nc_status
+  nc -v -l 127.0.0.1 5005 < nc_in > nc_out 2>nc_status &
   NCPID=$!
-  go-sleep 1s && kill "$NCPID" &
-  ipfs cat /ipfs/Qmabcdef --api /dns4/localhost/tcp/5005 || true
+
+  # Needed to "prime" nc
+  echo -n "" > nc_in
+
+  # Wait for it to start
+  head -1 nc_status
+'
+
+test_expect_success "can make http request against dns resolved nc server" '
+  cat >nc_in <<EOF
+HTTP/1.1 200 OK
+Content-Type: text/plain
+Content-Length: 1
+
+.
+EOF
+ipfs cat /ipfs/Qmabcdef --api /dns4/localhost/tcp/5005
+'
+
+test_expect_success "wait for nc to exit" '
+  wait $NCPID
 '
 
 test_expect_success "request was received by local nc server" '