document environ and filesystem

master
Daniel Kolesa 2017-04-05 20:53:14 +02:00
parent 480b7a56a4
commit 36332dff40
2 changed files with 111 additions and 6 deletions

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@ -1,6 +1,18 @@
/* Environment handling.
/** @defgroup Utilities
*
* This file is part of OctaSTD. See COPYING.md for futher information.
* @brief Miscellaneous utilities.
*
* @{
*/
/** @file environ.hh
*
* @brief A portable environment variable interface.
*
* Provides utility functions to portably get, set and unset environment
* variables.
*
* @copyright See COPYING.md in the project tree for further information.
*/
#ifndef OSTD_ENVIRON_HH
@ -17,10 +29,24 @@
#include "ostd/string.hh"
/* TODO: make POSIX version thread safe, the Windows version is... */
namespace ostd {
/** @addtogroup Utilities
* @{
*/
/** @brief Gets an environment variable.
*
* @returns std::nullopt when the variable doesn't exist, and an std::string
* containing the environment variable's value if it does.
*
* This function is thread-safe as long as the environment is not modified
* within the program. Calling to lower level functions to set environment
* vars as well as env_set() or env_unset() at the same time would introduce
* potential data races.
*
* @see env_set(), env_unset()
*/
inline std::optional<std::string> env_get(string_range name) {
char buf[256];
auto tbuf = to_temp_cstr(name, buf, sizeof(buf));
@ -47,6 +73,20 @@ inline std::optional<std::string> env_get(string_range name) {
#endif
}
/** @brief Sets an environment variable.
*
* If `update` is false, the environment variable will not be overwritten
* if it already exists. Keep in mind that true is still returned if the
* variable already exists and it's not being updated.
*
* This function is not thread safe. Do not call it from multiple threads
* and do not call it if a call to env_get() might be done from another
* thread at the time.
*
* @returns true on success, false on failure.
*
* @see env_get(), env_unset()
*/
inline bool env_set(
string_range name, string_range value, bool update = true
) {
@ -74,6 +114,16 @@ inline bool env_set(
return ret;
}
/** @brief Unsets an environment varible.
*
* This function is not thread safe. Do not call it from multiple threads
* and do not call it if a call to env_get() might be done from another
* thread at the time.
*
* @returns true on success, false on failure.
*
* @see env_get(), env_set()
*/
inline bool env_unset(string_range name) {
char buf[256];
if (name.size() < sizeof(buf)) {
@ -92,6 +142,10 @@ inline bool env_unset(string_range name) {
#endif
}
/** @} */
} /* namespace ostd */
#endif
/** @} */

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@ -1,6 +1,20 @@
/* Filesystem API for OctaSTD. Currently POSIX only.
/** @addtogroup Utilities
* @{
*/
/** @file filesystem.hh
*
* This file is part of OctaSTD. See COPYING.md for futher information.
* @brief Filesystem abstraction module.
*
* This module defines the namespace ostd::filesystem, which is either
* std::experimental::filesystem or std::filesystem depending on which
* is available. For portable applications, only use the subset of the
* module covered by both versions.
*
* It also provides range integration for directory iterators and
* ostd::format_traits specialization for std::filesystem::path.
*
* @copyright See COPYING.md in the project tree for further information.
*/
#ifndef OSTD_FILESYSTEM_HH
@ -25,26 +39,59 @@ namespace ostd {
namespace ostd {
/** @addtogroup Utilities
* @{
*/
/** @brief Range integration for std::filesystem::directory_iterator.
*
* Allows directory iterators to be made into ranges via ostd::iter().
*
* @see ostd::ranged_traits<filesystem::recursive_directory_iterator>
*/
template<>
struct ranged_traits<filesystem::directory_iterator> {
/** @brief The range type for the iterator. */
using range = iterator_range<filesystem::directory_iterator>;
/** @brief Creates a range for the iterator. */
static range iter(filesystem::directory_iterator const &r) {
return range{filesystem::begin(r), filesystem::end(r)};
}
};
/** @brief Range integration for std::filesystem::recursive_directory_iterator.
*
* Allows recursive directory iterators to be made into ranges via ostd::iter().
*
* @see ostd::ranged_traits<filesystem::directory_iterator>
*/
template<>
struct ranged_traits<filesystem::recursive_directory_iterator> {
/** @brief The range type for the iterator. */
using range = iterator_range<filesystem::recursive_directory_iterator>;
/** @brief Creates a range for the iterator. */
static range iter(filesystem::recursive_directory_iterator const &r) {
return range{filesystem::begin(r), filesystem::end(r)};
}
};
/** @brief ostd::format_traits specialization for std::filesystem::path.
*
* This allows paths to be formatted as strings. The value is formatted
* as if `path.string()` was formatted, using the exact ostd::format_spec.
*/
template<>
struct format_traits<filesystem::path> {
/** @brief Formats the path's string value.
*
* This calls exactly
*
* ~~~{.cc}
* fs.format_value(writer, p.string());
* ~~~
*/
template<typename R>
static void to_format(
filesystem::path const &p, R &writer, format_spec const &fs
@ -53,6 +100,10 @@ struct format_traits<filesystem::path> {
}
};
/** @} */
} /* namespace ostd */
#endif
/** @} */