ductape

Static template generator for C

ductape is static template generator with dynamic linking for C.

                                 +---------+                      (dlopen)
                           +---> |   .so   | ---------------------- load ------------------------+
+---------+    (ductape)   |     +---------+                                                     |
|  .html  | --- compile ---+                                                                     v
+---------+                |     +---------+                  +----------+      (cc)        +----------+
                           +---> |   .h    | --- include ---> |  main.c  | --- compile ---> |   main   |
                                 +---------+                  +----------+                  +----------+

Installation

git clone git@soophie.de:/srv/git/ductape
cd ductape
sudo make install

Quick Start

Create a macro.h file which needs to define DUC_OUT for storing the handle the content is later written to and DUC_WRITE which handles consuming and writing onto the handle.

The file can be extended with custom macros (like STRING, NUMBER, MARKDOWN, etc.), to simplify writing more complex templates.

#define DUC_OUT ((str_t *) out) // cast custom handle
#define DUC_WRITE($str) { str_append(DUC_OUT, $str); } // define custom write function

#define STRING DUC_WRITE

The template example.html is defined (could be any kind of language), which includes the previously defined macro header file, followed by the start of the template definition DUC_TEMPLDEF with the first parameter being the UID and succeeding with varies parameters which allow for injecting dynamic data. The end of the template is marked with DUC_ENDTEMPL. Inside the template definition. the content is rendered, while content outside will be ignored.

The symbol % marks the delimiter between template and C code. In order to use the delimiter in the template it needs to be repeated twice to escape the character. All parameters passed into the template are bound to the ctx variable.

% #include "macro.h" %

% DUC_TEMPLDEF(
  example,
  char *message;
) %

<p>% STRING(ctx->message) %</p>

% DUC_ENDTEMPL %

The template can be compiled with the the installed CLI command ductape. Simply pass a list of files to the command and it will generate the corresponding .h (header) and .so (shared library) files based on the specified UID of the template.

ductape example.html

Finally, a main function can be defined which imports the compiled example.h header file, which contains everything needed to dynamically render the template, such as the example_t context structure passed into the template, as well as the example_render function which renders the template into the specified out handle.

#include "example.h"

int main(void) {
  str_t out = STR_NULL;
  example_t ctx = {
    .message = "It works!",
  };
  int ret = example_render(&out, &ctx);
  if (ret == 0) {
    printf("%s", (char *) str_get(&out))
    str_free(&out);
  }
  return ret;
}