api-function-example.md
2.1 KB
Example main.c
#include <stdio.h>
#include <stdint.h>
#include "sass/context.h"
union Sass_Value* call_fn_foo(const union Sass_Value* s_args, Sass_Function_Entry cb, struct Sass_Compiler* comp)
{
// get context/option struct associated with this compiler
struct Sass_Context* ctx = sass_compiler_get_context(comp);
struct Sass_Options* opts = sass_compiler_get_options(comp);
// get information about previous importer entry from the stack
Sass_Import_Entry import = sass_compiler_get_last_import(comp);
const char* prev_abs_path = sass_import_get_abs_path(import);
const char* prev_imp_path = sass_import_get_imp_path(import);
// get the cookie from function descriptor
void* cookie = sass_function_get_cookie(cb);
// we actually abuse the void* to store an "int"
return sass_make_number((intptr_t)cookie, "px");
}
int main( int argc, const char* argv[] )
{
// get the input file from first argument or use default
const char* input = argc > 1 ? argv[1] : "styles.scss";
// create the file context and get all related structs
struct Sass_File_Context* file_ctx = sass_make_file_context(input);
struct Sass_Context* ctx = sass_file_context_get_context(file_ctx);
struct Sass_Options* ctx_opt = sass_context_get_options(ctx);
// allocate a custom function caller
Sass_Function_Entry fn_foo =
sass_make_function("foo()", call_fn_foo, (void*)42);
// create list of all custom functions
Sass_Function_List fn_list = sass_make_function_list(1);
sass_function_set_list_entry(fn_list, 0, fn_foo);
sass_option_set_c_functions(ctx_opt, fn_list);
// context is set up, call the compile step now
int status = sass_compile_file_context(file_ctx);
// print the result or the error to the stdout
if (status == 0) puts(sass_context_get_output_string(ctx));
else puts(sass_context_get_error_message(ctx));
// release allocated memory
sass_delete_file_context(file_ctx);
// exit status
return status;
}
Compile main.c
gcc -c main.c -o main.o
gcc -o sample main.o -lsass
echo "foo { margin: foo(); }" > foo.scss
./sample foo.scss => "foo { margin: 42px }"