ngx_rtmp_variables.c

/*
 * Copyright (C) 2017 Gnolizuh
 */

#include <ngx_rtmp_variables.h>


ngx_rtmp_variable_t *
ngx_rtmp_add_variable(ngx_conf_t *cf, ngx_str_t *name, ngx_uint_t flags)
{
    ngx_int_t                   rc;
    ngx_uint_t                  i;
    ngx_hash_key_t             *key;
    ngx_rtmp_variable_t        *v;
    ngx_rtmp_core_main_conf_t  *cmcf;

    if (name->len == 0) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "invalid variable name \"$\"");
        return NULL;
    }

    cmcf = ngx_rtmp_conf_get_module_main_conf(cf, ngx_rtmp_core_module);

    key = cmcf->variables_keys->keys.elts;
    for (i = 0; i < cmcf->variables_keys->keys.nelts; i++) {
        if (name->len != key[i].key.len
            || ngx_strncasecmp(name->data, key[i].key.data, name->len) != 0)
        {
            continue;
        }

        v = key[i].value;

        if (!(v->flags & NGX_RTMP_VAR_CHANGEABLE)) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "the duplicate \"%V\" variable", name);
            return NULL;
        }

        return v;
    }

    v = ngx_palloc(cf->pool, sizeof(ngx_rtmp_variable_t));
    if (v == NULL) {
        return NULL;
    }

    v->name.len = name->len;
    v->name.data = ngx_pnalloc(cf->pool, name->len);
    if (v->name.data == NULL) {
        return NULL;
    }

    ngx_strlow(v->name.data, name->data, name->len);

    v->set_handler = NULL;
    v->get_handler = NULL;
    v->data = 0;
    v->flags = flags;
    v->index = 0;

    rc = ngx_hash_add_key(cmcf->variables_keys, &v->name, v, 0);

    if (rc == NGX_ERROR) {
        return NULL;
    }

    if (rc == NGX_BUSY) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "conflicting variable name \"%V\"", name);
        return NULL;
    }

    return v;
}


ngx_int_t
ngx_rtmp_get_variable_index(ngx_conf_t *cf, ngx_str_t *name)
{
    ngx_uint_t                  i;
    ngx_rtmp_variable_t        *v;
    ngx_rtmp_core_main_conf_t  *cmcf;

    if (name->len == 0) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "invalid variable name \"$\"");
        return NGX_ERROR;
    }

    cmcf = ngx_rtmp_conf_get_module_main_conf(cf, ngx_rtmp_core_module);

    v = cmcf->variables.elts;

    if (v == NULL) {
        if (ngx_array_init(&cmcf->variables, cf->pool, 4,
                           sizeof(ngx_rtmp_variable_t))
            != NGX_OK)
        {
            return NGX_ERROR;
        }

    } else {
        for (i = 0; i < cmcf->variables.nelts; i++) {
            if (name->len != v[i].name.len
                || ngx_strncasecmp(name->data, v[i].name.data, name->len) != 0)
            {
                continue;
            }

            return i;
        }
    }

    v = ngx_array_push(&cmcf->variables);
    if (v == NULL) {
        return NGX_ERROR;
    }

    v->name.len = name->len;
    v->name.data = ngx_pnalloc(cf->pool, name->len);
    if (v->name.data == NULL) {
        return NGX_ERROR;
    }

    ngx_strlow(v->name.data, name->data, name->len);

    v->set_handler = NULL;
    v->get_handler = NULL;
    v->data = 0;
    v->flags = 0;
    v->index = cmcf->variables.nelts - 1;

    return v->index;
}


#if (NGX_PCRE)

static ngx_int_t
ngx_rtmp_variable_not_found(ngx_rtmp_session_t *s, ngx_rtmp_variable_value_t *v,
    uintptr_t data)
{
    v->not_found = 1;
    return NGX_OK;
}


ngx_rtmp_regex_t *
ngx_rtmp_regex_compile(ngx_conf_t *cf, ngx_regex_compile_t *rc)
{
    u_char                     *p;
    size_t                      size;
    ngx_str_t                   name;
    ngx_uint_t                  i, n;
    ngx_rtmp_variable_t        *v;
    ngx_rtmp_regex_t           *re;
    ngx_rtmp_regex_variable_t  *rv;
    ngx_rtmp_core_main_conf_t  *cmcf;

    rc->pool = cf->pool;

    if (ngx_regex_compile(rc) != NGX_OK) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%V", &rc->err);
        return NULL;
    }

    re = ngx_pcalloc(cf->pool, sizeof(ngx_rtmp_regex_t));
    if (re == NULL) {
        return NULL;
    }

    re->regex = rc->regex;
    re->ncaptures = rc->captures;
    re->name = rc->pattern;

    cmcf = ngx_rtmp_conf_get_module_main_conf(cf, ngx_rtmp_core_module);
    cmcf->ncaptures = ngx_max(cmcf->ncaptures, re->ncaptures);

    n = (ngx_uint_t) rc->named_captures;

    if (n == 0) {
        return re;
    }

    rv = ngx_palloc(rc->pool, n * sizeof(ngx_rtmp_regex_variable_t));
    if (rv == NULL) {
        return NULL;
    }

    re->variables = rv;
    re->nvariables = n;

    size = rc->name_size;
    p = rc->names;

    for (i = 0; i < n; i++) {
        rv[i].capture = 2 * ((p[0] << 8) + p[1]);

        name.data = &p[2];
        name.len = ngx_strlen(name.data);

        v = ngx_rtmp_add_variable(cf, &name, NGX_RTMP_VAR_CHANGEABLE);
        if (v == NULL) {
            return NULL;
        }

        rv[i].index = ngx_rtmp_get_variable_index(cf, &name);
        if (rv[i].index == NGX_ERROR) {
            return NULL;
        }

        v->get_handler = ngx_rtmp_variable_not_found;

        p += size;
    }

    return re;
}

#endif