#ifndef SYSTEM_H
#define SYSTEM_H

/* Routines for interacting with the system, mainly executing processes and
 * dealing with the file system. */

void __sys_check(int cond, const char *prefix, const char *file, int line);

#define sys_check(COND, PREFIX)	__sys_check(COND, PREFIX, __FILE__, __LINE__)

/* Used when encrypting or decrypting a file, see the copy_file_with_encryption
 * function. */
enum encrypt {
	ENCRYPT,
	DECRYPT
};

/* Return whether PATH exists in the file system. Exit if any non-"file not
 * fount" error occurs. */
int file_exists(const char *path);

/* Copy the file whose path is IN at path OUT. OUT is created or overwritten if
 * needed. */
void copy_file(const char *in, const char *out);

/* Like copy_file but with encryption, which is managed using GPG.  */
void copy_file_with_encryption(const char *in, const char *out, enum encrypt encrypt);

/* Execute command in a child process, then wait for the child to exit before
 * returning. If any error occurs, including in the child process, then if EXIT
 * is non-zero, exit, else return -1. Return 0 on success. */
int ftag_execvp(char *const *cmd, int can_exit);

/* Create a temporary file containing INITIAL_CONTENT and open the editor to
 * edit it, then return the edited string. */
char *edit(const char *initial_content);

/* Get the content of the open file FD as a heap-allocated string. The offset of
 * FD is set to zero as a side effect. */
char *file_to_string(int fd);

#endif