Browse Source Download (without any required ccan dependencies)

Module:

take

Summary:

routines to mark pointers to be consumed by called functions.

Author:

Rusty Russell <rusty@rustcorp.com.au>

Dependencies:

Description:

This code helps to implement ownership transfer on a per-arg basis: the caller wraps the pointer argument in take() and the callee checks taken() to see if it should consume it.

Example:

// Given "foo/bar.c" outputs basename is bar.c
#include <ccan/take/take.h>
#include <string.h>

// Dumb basename program and driver.
static char *base(const char *file TAKES)
{
        const char *p = strrchr(file, '/');
        if (!p) 
                p = file;
        else
                p++;

        // Use arg in place if we're allowed.
        if (taken(file))
                return memmove((char *)file, p, strlen(p)+1);
        else
                return strdup(p);
}

int main(int argc, char *argv[])
{
        char *b;

        if (argc > 1) // Mangle in place.
                b = base(take(argv[1]));
        else
                b = base("test/string");

        printf("basename is %s\n", b);
        return 0;
}

License:

CC0 (Public domain)