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#include "config.h"
#include <stdio.h>
#include <string.h>
/**
* talloc - tree allocator routines
*
* Talloc is a hierarchical memory pool system with destructors: you keep your
* objects in heirarchies reflecting their lifetime. Every pointer returned
* from talloc() is itself a valid talloc context, from which other talloc()s
* can be attached. This means you can do this:
*
* struct foo *X = talloc(mem_ctx, struct foo);
* X->name = talloc_strdup(X, "foo");
*
* and the pointer X->name would be a "child" of the talloc context "X" which
* is itself a child of mem_ctx. So if you do talloc_free(mem_ctx) then it is
* all destroyed, whereas if you do talloc_free(X) then just X and X->name are
* destroyed, and if you do talloc_free(X->name) then just the name element of
* X is destroyed.
*
* If you think about this, then what this effectively gives you is an n-ary
* tree, where you can free any part of the tree with talloc_free().
*
* Talloc has been measured with a time overhead of around 4% over glibc
* malloc, and 48/80 bytes per allocation (32/64 bit).
*
* This version is based on svn://svnanon.samba.org/samba/branches/SAMBA_4_0/source/lib/talloc revision 23158.
*
* Example:
* #include <stdio.h>
* #include <stdarg.h>
* #include <err.h>
* #include <ccan/talloc/talloc.h>
*
* // A structure containing a popened command.
* struct command
* {
* FILE *f;
* const char *command;
* };
*
* // When struct command is freed, we also want to pclose pipe.
* static int close_cmd(struct command *cmd)
* {
* pclose(cmd->f);
* // 0 means "we succeeded, continue freeing"
* return 0;
* }
*
* // This function opens a writable pipe to the given command.
* static struct command *open_output_cmd(const void *ctx,
* const char *fmt, ...)
* {
* va_list ap;
* struct command *cmd = talloc(ctx, struct command);
*
* if (!cmd)
* return NULL;
*
* va_start(ap, fmt);
* cmd->command = talloc_vasprintf(cmd, fmt, ap);
* va_end(ap);
* if (!cmd->command) {
* talloc_free(cmd);
* return NULL;
* }
*
* cmd->f = popen(cmd->command, "w");
* if (!cmd->f) {
* talloc_free(cmd);
* return NULL;
* }
* talloc_set_destructor(cmd, close_cmd);
* return cmd;
* }
*
* int main(int argc, char *argv[])
* {
* struct command *cmd;
*
* if (argc != 2)
* errx(1, "Usage: %s <command>\n", argv[0]);
*
* cmd = open_output_cmd(NULL, "%s hello", argv[1]);
* if (!cmd)
* err(1, "Running '%s hello'", argv[1]);
* fprintf(cmd->f, "This is a test\n");
* talloc_free(cmd);
* return 0;
* }
*
* License: LGPL (v2.1 or any later version)
*/
int main(int argc, char *argv[])
{
if (argc != 2)
return 1;
if (strcmp(argv[1], "depends") == 0) {
printf("ccan/compiler\n");
printf("ccan/typesafe_cb\n");
return 0;
}
if (strcmp(argv[1], "testdepends") == 0) {
printf("ccan/failtest\n");
return 0;
}
return 1;
}
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