libunit-wasm: Remove the idx argument from luw_http_add_header()

This was used to specify the index of the response header being added,
starting at 0 and incrementing by one for each header.

Instead of having the programmer specify this, track it internally.

We add an extra check in luw_http_add_header() to make sure we aren't
trying to add more headers than we said with luw_http_init_headers(), if
we are, simply return.

This updates the API-C.md and the various examples and 'rusty' API
wrapper.

Suggested-by: Liam Crilly <liam@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>

1 files changed, 6 insertions, 6 deletions

diff --git a/API-C.md b/API-C.md
index 1899f05..c0cfc02 100644
--- a/API-C.md
+++ b/API-C.md
@@ -212,6 +212,9 @@ typedef struct {
 
         /* points to the end of ctx->req_buf */
         u8 *reqp;
+
+        /* tracks the response header index number */
+        s32 resp_hdr_idx;
 } luw_ctx_t;
 ```
 
@@ -864,14 +867,11 @@ luw_http_init_headers(ctx, 2, 0);
 ### luw_http_add_header
 
 ```C
-void luw_http_add_header(luw_ctx_t *ctx, u16 idx, const char *name,
-                         const char *value);
+void luw_http_add_header(luw_ctx_t *ctx, const char *name, const char *value);
 ```
 
 This function is used to add a header to the response.
 
-_idx_ is the index (starting at 0) of the header we are adding.
-
 _name_ is the name of the header.
 
 _value_ is the value of the header.
@@ -882,8 +882,8 @@ Example
 char clen[32];
 /* ... */
 snprintf(clen, sizeof(clen), "%lu", luw_get_response_data_size(&ctx));
-luw_http_add_header(&ctx, 0, "Content-Type", "text/plain");
-luw_http_add_header(&ctx, 1, "Content-Length", clen);
+luw_http_add_header(&ctx, "Content-Type", "text/plain");
+luw_http_add_header(&ctx, "Content-Length", clen);
 ```
 
 ### luw_http_send_headers