libutil: implement a realPath() utility

Just a wrapper around POSIX realpath().

Change-Id: I2593770285dbae573eace490efce5b272b00b001
This commit is contained in:
Qyriad 2024-07-12 16:15:33 -06:00
parent 1eb5d22132
commit d9c51ec4e5
2 changed files with 35 additions and 0 deletions

View file

@ -1,4 +1,5 @@
#include <sys/time.h>
#include <cstdlib>
#include <filesystem>
#include <atomic>
@ -106,6 +107,24 @@ Path canonPath(PathView path, bool resolveSymlinks)
return s.empty() ? "/" : std::move(s);
}
Path realPath(Path const & path)
{
// With nullptr, realpath() malloc's and returns a new c-string.
char * resolved = realpath(path.c_str(), nullptr);
int saved = errno;
if (resolved == nullptr) {
throw SysError(saved, "cannot get realpath for '%s'", path);
}
Finally const _free([&] { free(resolved); });
// There's not really a from_raw_parts() for std::string.
// The copy is not a big deal.
Path ret(resolved);
return ret;
}
void chmodPath(const Path & path, mode_t mode)
{
if (chmod(path.c_str(), mode) == -1)

View file

@ -46,6 +46,22 @@ Path absPath(Path path,
*/
Path canonPath(PathView path, bool resolveSymlinks = false);
/**
* Resolves a file path to a fully absolute path with no symbolic links.
*
* @param path The path to resolve. If it is relative, it will be resolved relative
* to the process's current directory.
*
* @note This is not a pure function; it performs this resolution by querying
* the filesystem.
*
* @note @ref path sadly must be (a reference to) an owned string, as std::string_view
* are not valid C strings...
*
* @return The fully resolved path.
*/
Path realPath(Path const & path);
/**
* Change the permissions of a path
* Not called `chmod` as it shadows and could be confused with