diff options
Diffstat (limited to '')
| -rw-r--r-- | src/base/auto_fd.hh | 168 |
1 files changed, 34 insertions, 134 deletions
diff --git a/src/base/auto_fd.hh b/src/base/auto_fd.hh index da4a582..9fb3c91 100644 --- a/src/base/auto_fd.hh +++ b/src/base/auto_fd.hh @@ -32,16 +32,11 @@ #ifndef auto_fd_hh #define auto_fd_hh -#include <exception> -#include <new> #include <string> -#include <errno.h> #include <fcntl.h> -#include <sys/select.h> -#include <unistd.h> -#include "base/lnav_log.hh" +#include "base/intern_string.hh" #include "base/result.h" /** @@ -59,19 +54,7 @@ public: * contains the reader end of the pipe and the second contains the writer. * @return The result of the pipe(2) function. */ - static int pipe(auto_fd* af) - { - int retval, fd[2]; - - require(af != nullptr); - - if ((retval = ::pipe(fd)) == 0) { - af[0] = fd[0]; - af[1] = fd[1]; - } - - return retval; - } + static int pipe(auto_fd* af); /** * dup(2) the given file descriptor and wrap it in an auto_fd. @@ -79,27 +62,16 @@ public: * @param fd The file descriptor to duplicate. * @return A new auto_fd that contains the duplicated file descriptor. */ - static auto_fd dup_of(int fd) - { - if (fd == -1) { - return auto_fd{}; - } + static auto_fd dup_of(int fd); - auto new_fd = ::dup(fd); - - if (new_fd == -1) { - throw std::bad_alloc(); - } - - return auto_fd(new_fd); - } + static Result<auto_fd, std::string> openpt(int flags); /** * Construct an auto_fd to manage the given file descriptor. * * @param fd The file descriptor to be managed. */ - explicit auto_fd(int fd = -1) : af_fd(fd) { require(fd >= -1); } + explicit auto_fd(int fd = -1); /** * Non-const copy constructor. Management of the file descriptor will be @@ -108,7 +80,7 @@ public: * * @param af The source of the file descriptor. */ - auto_fd(auto_fd&& af) noexcept : af_fd(af.release()) {} + auto_fd(auto_fd&& af) noexcept; /** * Const copy constructor. The file descriptor from the source will be @@ -118,21 +90,12 @@ public: */ auto_fd(const auto_fd& af) = delete; - auto_fd dup() const - { - int new_fd; - - if (this->af_fd == -1 || (new_fd = ::dup(this->af_fd)) == -1) { - throw std::bad_alloc(); - } - - return auto_fd{new_fd}; - } + auto_fd dup() const; /** * Destructor that will close the file descriptor managed by this object. */ - ~auto_fd() { this->reset(); } + ~auto_fd(); /** @return The file descriptor as a plain integer. */ operator int() const { return this->af_fd; } @@ -144,13 +107,7 @@ public: * @param fd The file descriptor to store in this object. * @return *this */ - auto_fd& operator=(int fd) - { - require(fd >= -1); - - this->reset(fd); - return *this; - } + auto_fd& operator=(int fd); /** * Transfer management of the given file descriptor to this object. @@ -194,39 +151,21 @@ public: */ int get() const { return this->af_fd; } + bool has_value() const { return this->af_fd != -1; } + /** * Closes the current file descriptor and replaces its value with the given * one. * * @param fd The new file descriptor to be managed. */ - void reset(int fd = -1) - { - require(fd >= -1); - - if (this->af_fd != fd) { - if (this->af_fd != -1) { - switch (this->af_fd) { - case STDIN_FILENO: - case STDOUT_FILENO: - case STDERR_FILENO: - break; - default: - close(this->af_fd); - break; - } - } - this->af_fd = fd; - } - } + void reset(int fd = -1); - void close_on_exec() const - { - if (this->af_fd == -1) { - return; - } - log_perror(fcntl(this->af_fd, F_SETFD, FD_CLOEXEC)); - } + Result<void, std::string> write_fully(string_fragment sf); + + void close_on_exec() const; + + void non_blocking() const; private: int af_fd; /*< The managed file descriptor. */ @@ -234,32 +173,30 @@ private: class auto_pipe { public: - static Result<auto_pipe, std::string> for_child_fd(int child_fd) + static Result<auto_pipe, std::string> for_child_fd(int child_fd); + + template<typename... ARGS> + static Result<std::array<auto_pipe, sizeof...(ARGS)>, std::string> + for_child_fds(ARGS... args) { - auto_pipe retval(child_fd); + std::array<auto_pipe, sizeof...(ARGS)> retval; - if (retval.open() == -1) { - return Err(std::string(strerror(errno))); + size_t index = 0; + for (const auto child_fd : {args...}) { + auto open_res = for_child_fd(child_fd); + if (open_res.isErr()) { + return Err(open_res.unwrapErr()); + } + + retval[index++] = open_res.unwrap(); } return Ok(std::move(retval)); } - explicit auto_pipe(int child_fd = -1, int child_flags = O_RDONLY) - : ap_child_flags(child_flags), ap_child_fd(child_fd) - { - switch (child_fd) { - case STDIN_FILENO: - this->ap_child_flags = O_RDONLY; - break; - case STDOUT_FILENO: - case STDERR_FILENO: - this->ap_child_flags = O_WRONLY; - break; - } - } + explicit auto_pipe(int child_fd = -1, int child_flags = O_RDONLY); - int open() { return auto_fd::pipe(this->ap_fd); } + int open(); void close() { @@ -271,44 +208,7 @@ public: auto_fd& write_end() { return this->ap_fd[1]; } - void after_fork(pid_t child_pid) - { - int new_fd; - - switch (child_pid) { - case -1: - this->close(); - break; - case 0: - if (this->ap_child_flags == O_RDONLY) { - this->write_end().reset(); - if (this->read_end().get() == -1) { - this->read_end() = ::open("/dev/null", O_RDONLY); - } - new_fd = this->read_end().get(); - } else { - this->read_end().reset(); - if (this->write_end().get() == -1) { - this->write_end() = ::open("/dev/null", O_WRONLY); - } - new_fd = this->write_end().get(); - } - if (this->ap_child_fd != -1) { - if (new_fd != this->ap_child_fd) { - dup2(new_fd, this->ap_child_fd); - this->close(); - } - } - break; - default: - if (this->ap_child_flags == O_RDONLY) { - this->read_end().reset(); - } else { - this->write_end().reset(); - } - break; - } - } + void after_fork(pid_t child_pid); int ap_child_flags; int ap_child_fd; |