ngx_http_ssi_filter_module.c

Nginx是一个高性能的HTTP和反向代理服务器

        b = cl->buf;
    }
#endif

    rc = ngx_http_next_body_filter(r, ctx->out);

    if (ctx->busy == NULL) {
        ctx->busy = ctx->out;

    } else {
        for (cl = ctx->busy; cl->next; cl = cl->next) { /* void */ }
        cl->next = ctx->out;
    }

    ctx->out = NULL;
    ctx->last_out = &ctx->out;

    while (ctx->busy) {

        cl = ctx->busy;
        b = cl->buf;

        if (ngx_buf_size(b) != 0) {
            break;
        }

#if (NGX_HAVE_WRITE_ZEROCOPY)
        if (b->zerocopy_busy) {
            break;
        }
#endif

        if (b->shadow) {
            b->shadow->pos = b->shadow->last;
        }

        ctx->busy = cl->next;

        if (ngx_buf_in_memory(b) || b->in_file) {
            /* add data bufs only to the free buf chain */

            cl->next = ctx->free;
            ctx->free = cl;
        }
    }

    if (ctx->in || ctx->buf) {
        r->buffered |= NGX_HTTP_SSI_BUFFERED;

    } else {
        r->buffered &= ~NGX_HTTP_SSI_BUFFERED;
    }

    return rc;
}


static ngx_int_t
ngx_http_ssi_parse(ngx_http_request_t *r, ngx_http_ssi_ctx_t *ctx)
{
    u_char                *p, *value, *last, *copy_end, ch;
    size_t                 looked;
    ngx_http_ssi_state_e   state;

    state = ctx->state;
    looked = ctx->looked;
    last = ctx->buf->last;
    copy_end = ctx->copy_end;

    for (p = ctx->pos; p < last; p++) {

        ch = *p;

        if (state == ssi_start_state) {

            /* the tight loop */

            for ( ;; ) {
                if (ch == '<') {
                    copy_end = p;
                    looked = 1;
                    state = ssi_tag_state;

                    goto tag_started;
                }

                if (++p == last) {
                    break;
                }

                ch = *p;
            }

            ctx->state = state;
            ctx->pos = p;
            ctx->looked = looked;
            ctx->copy_end = p;

            if (ctx->copy_start == NULL) {
                ctx->copy_start = ctx->buf->pos;
            }

            return NGX_AGAIN;

        tag_started:

            continue;
        }

        switch (state) {

        case ssi_start_state:
            break;

        case ssi_tag_state:
            switch (ch) {
            case '!':
                looked = 2;
                state = ssi_comment0_state;
                break;

            case '<':
                copy_end = p;
                break;

            default:
                copy_end = p;
                looked = 0;
                state = ssi_start_state;
                break;
            }

            break;

        case ssi_comment0_state:
            switch (ch) {
            case '-':
                looked = 3;
                state = ssi_comment1_state;
                break;

            case '<':
                copy_end = p;
                looked = 1;
                state = ssi_tag_state;
                break;

            default:
                copy_end = p;
                looked = 0;
                state = ssi_start_state;
                break;
            }

            break;

        case ssi_comment1_state:
            switch (ch) {
            case '-':
                looked = 4;
                state = ssi_sharp_state;
                break;

            case '<':
                copy_end = p;
                looked = 1;
                state = ssi_tag_state;
                break;

            default:
                copy_end = p;
                looked = 0;
                state = ssi_start_state;
                break;
            }

            break;

        case ssi_sharp_state:
            switch (ch) {
            case '#':
                if (p - ctx->pos < 4) {
                    ctx->saved = 0;
                }
                looked = 0;
                state = ssi_precommand_state;
                break;

            case '<':
                copy_end = p;
                looked = 1;
                state = ssi_tag_state;
                break;

            default:
                copy_end = p;
                looked = 0;
                state = ssi_start_state;
                break;
            }

            break;

        case ssi_precommand_state:
            switch (ch) {
            case ' ':
            case CR:
            case LF:
            case '\t':
                break;

            default:
                ctx->command.len = 1;
                ctx->command.data = ngx_palloc(r->pool,
                                               NGX_HTTP_SSI_COMMAND_LEN);
                if (ctx->command.data == NULL) {
                    return NGX_ERROR;
                }

                ctx->command.data[0] = ch;

                ctx->key = 0;
                ctx->key = ngx_hash(ctx->key, ch);

                ctx->params.nelts = 0;

                state = ssi_command_state;
                break;
            }

            break;

        case ssi_command_state:
            switch (ch) {
            case ' ':
            case CR:
            case LF:
            case '\t':
                state = ssi_preparam_state;
                break;

            case '-':
                state = ssi_comment_end0_state;
                break;

            default:
                if (ctx->command.len == NGX_HTTP_SSI_COMMAND_LEN) {
                    ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                                  "the \"%V%c...\" SSI command is too long",
                                  &ctx->command, ch);

                    state = ssi_error_state;
                    break;
                }

                ctx->command.data[ctx->command.len++] = ch;
                ctx->key = ngx_hash(ctx->key, ch);
            }

            break;

        case ssi_preparam_state:
            switch (ch) {
            case ' ':
            case CR:
            case LF:
            case '\t':
                break;

            case '-':
                state = ssi_comment_end0_state;
                break;

            default:
                ctx->param = ngx_array_push(&ctx->params);
                if (ctx->param == NULL) {
                    return NGX_ERROR;
                }

                ctx->param->key.len = 1;
                ctx->param->key.data = ngx_palloc(r->pool,
                                                  NGX_HTTP_SSI_PARAM_LEN);
                if (ctx->param->key.data == NULL) {
                    return NGX_ERROR;
                }

                ctx->param->key.data[0] = ch;

                ctx->param->value.len = 0;

                if (ctx->value_buf == NULL) {
                    ctx->param->value.data = ngx_palloc(r->pool,
                                                        ctx->value_len);
                    if (ctx->param->value.data == NULL) {
                        return NGX_ERROR;
                    }

                } else {
                    ctx->param->value.data = ctx->value_buf;
                }

                state = ssi_param_state;
                break;
            }

            break;

        case ssi_param_state:
            switch (ch) {
            case ' ':
            case CR:
            case LF:
            case '\t':
                state = ssi_preequal_state;
                break;

            case '=':
                state = ssi_prevalue_state;
                break;

            case '-':
                state = ssi_error_end0_state;

                ctx->param->key.data[ctx->param->key.len++] = ch;
                ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                              "invalid \"%V\" parameter in \"%V\" SSI command",
                              &ctx->param->key, &ctx->command);
                break;

            default:
                if (ctx->param->key.len == NGX_HTTP_SSI_PARAM_LEN) {
                    state = ssi_error_state;
                    ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                                  "too long \"%V%c...\" parameter in "
                                  "\"%V\" SSI command",
                                  &ctx->param->key, ch, &ctx->command);
                    break;
                }

                ctx->param->key.data[ctx->param->key.len++] = ch;
            }

            break;

        case ssi_preequal_state:
            switch (ch) {
            case ' ':
            case CR:
            case LF:
            case '\t':
                break;

            case '=':
                state = ssi_prevalue_state;
                break;

            default:
                if (ch == '-') {
                    state = ssi_error_end0_state;
                } else {
                    state = ssi_error_state;
                }

                ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                              "unexpected \"%c\" symbol after \"%V\" "
                              "parameter in \"%V\" SSI command",
                              ch, &ctx->param->key, &ctx->command);
                break;
            }

            break;

        case ssi_prevalue_state:
            switch (ch) {
            case ' ':
            case CR:
            case LF:
            case '\t':
                break;

            case '"':
                state = ssi_double_quoted_value_state;
                break;

            case '\'':
                state = ssi_quoted_value_state;
                break;

            default:
                if (ch == '-') {
                    state = ssi_error_end0_state;
                } else {
                    state = ssi_error_state;
                }

                ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                              "unexpected \"%c\" symbol before value of "
                              "\"%V\" parameter in \"%V\" SSI command",
                              ch, &ctx->param->key, &ctx->command);
                break;
            }

            break;

        case ssi_double_quoted_value_state:
            switch (ch) {
            case '"':
                state = ssi_postparam_state;
                break;

            case '\\':
                ctx->saved_state = ssi_double_quoted_value_state;
                state = ssi_quoted_symbol_state;

                /* fall through */

            default:
                if (ctx->param->value.len == ctx->value_len) {
                    ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                                  "too long \"%V%c...\" value of \"%V\" "
                                  "parameter in \"%V\" SSI command",
                                  &ctx->param->value, ch, &ctx->param->key,
                                  &ctx->command);
                    state = ssi_error_state;
                    break;
                }

                ctx->param->value.data[ctx->param->value.len++] = ch;
            }

            break;

        case ssi_quoted_value_state:
            switch (ch) {
            case '\'':
                state = ssi_postparam_state;
                break;

            case '\\':
                ctx->saved_state = ssi_quoted_value_state;
                state = ssi_quoted_symbol_state;

                /* fall through */

            default:
                if (ctx->param->value.len == ctx->value_len) {
                    ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                                  "too long \"%V%c...\" value of \"%V\" "
                                  "parameter in \"%V\" SSI command",
                                  &ctx->param->value, ch, &ctx->param->key,
                                  &ctx->command);
                    state = ssi_error_state;
                    break;
                }

                ctx->param->value.data[ctx->param->value.len++] = ch;
            }

            break;

        case ssi_quoted_symbol_state:
            state = ctx->saved_state;

            ctx->param->value.data[ctx->param->value.len++] = ch;

            break;

        case ssi_postparam_state:

            if (ctx->param->value.len + 1 < ctx->value_len / 2) {