restyle exec module to match project style

Reduces lint errors from 121 to 59 (-51%). Line count from 1578 to 1290 (-18%).

Another step in resolving issue #2902.

src/exec.h

@@ -1,73 +1,51 @@
-/** \file exec.h
-  Prototypes for functions for executing a program
-*/
-
+// Prototypes for functions for executing a program.
 #ifndef FISH_EXEC_H
 #define FISH_EXEC_H
 
+#include <stdbool.h>
 #include <stddef.h>
 #include <vector>
-#include <stdbool.h>
 
 #include "common.h"
 
-/**
-   pipe redirection error message
-*/
+/// Pipe redirection error message.
 #define PIPE_ERROR _(L"An error occurred while setting up pipe")
 
-/**
-  Execute the processes specified by j.
-
-   I've put a fair bit of work into making builtins behave like other
-   programs as far as pipes are concerned. Unlike i.e. bash, builtins
-   can pipe to other builtins with arbitrary amounts of data, and so
-   on. To do this, after a builtin is run in the real process, it
-   forks and a dummy process is created, responsible for writing the
-   output of the builtin. This is surprisingly cheap on my computer,
-   probably because of the marvels of copy on write forking.
-
-   This rule is short circuited in the case where a builtin does not
-   output to a pipe and does in fact not output anything. The speed
-   improvement from this optimization is not noticable on a normal
-   computer/OS in regular use, but the promiscous amounts of forking
-   that resulted was responsible for a huge slowdown when using
-   Valgrind as well as when doing complex command-specific
-   completions.
-
-
-*/
+/// Execute the processes specified by j.
+///
+/// I've put a fair bit of work into making builtins behave like other programs as far as pipes are
+/// concerned. Unlike i.e. bash, builtins can pipe to other builtins with arbitrary amounts of data,
+/// and so on. To do this, after a builtin is run in the real process, it forks and a dummy process
+/// is created, responsible for writing the output of the builtin. This is surprisingly cheap on my
+/// computer, probably because of the marvels of copy on write forking.
+///
+/// This rule is short circuited in the case where a builtin does not output to a pipe and does in
+/// fact not output anything. The speed improvement from this optimization is not noticable on a
+/// normal computer/OS in regular use, but the promiscous amounts of forking that resulted was
+/// responsible for a huge slowdown when using Valgrind as well as when doing complex
+/// command-specific completions.
 class job_t;
 class parser_t;
 void exec_job(parser_t &parser, job_t *j);
 
-/**
-  Evaluate the expression cmd in a subshell, add the outputs into the
-  list l. On return, the status flag as returned bu \c
-  proc_gfet_last_status will not be changed.
-
-  \param cmd the command to execute
-  \param outputs The list to insert output into.
-
-  \return the status of the last job to exit, or -1 if en error was encountered.
-*/
+/// Evaluate the expression cmd in a subshell, add the outputs into the list l. On return, the
+/// status flag as returned bu \c proc_gfet_last_status will not be changed.
+///
+/// \param cmd the command to execute
+/// \param outputs The list to insert output into.
+///
+/// \return the status of the last job to exit, or -1 if en error was encountered.
 int exec_subshell(const wcstring &cmd, std::vector<wcstring> &outputs, bool preserve_exit_status);
 int exec_subshell(const wcstring &cmd, bool preserve_exit_status);
 
-
-/**
-   Loops over close until the syscall was run without being
-   interrupted.
-*/
+/// Loops over close until the syscall was run without being interrupted.
 void exec_close(int fd);
 
-/**
-   Call pipe(), and add resulting fds to open_fds, the list of opened
-   file descriptors for pipes. The pipes are marked CLO_EXEC.
-*/
+/// Call pipe(), and add resulting fds to open_fds, the list of opened file descriptors for pipes.
+/// The pipes are marked CLO_EXEC.
 int exec_pipe(int fd[2]);
 
-/** Gets the interpreter for a given command */
+/// Gets the interpreter for a given command.
 char *get_interpreter(const char *command, char *interpreter, size_t buff_size);
 
 #endif