From 8a4fcdee4dce240c4a2f8369f0aba8733234245b Mon Sep 17 00:00:00 2001
From: Gabe Black <gabeblack@google.com>
Date: Tue, 7 Apr 2020 00:40:27 -0700
Subject: [PATCH] util: Make m5 commands return a bool instead of calling
 usage.

By delegating actually calling usage() elsewhere, we can remove a dependency
from the commands themselves, and also make testing easier since we won't
exit() every time we call a command with bad arguments.

Change-Id: I6b8e2cb77ce0456b16673f10349362cc53218bba
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/27565
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
---
 util/m5/src/command.cc                | 3 +--
 util/m5/src/command.hh                | 2 +-
 util/m5/src/command.test.cc           | 6 ++++--
 util/m5/src/command/addsymbol.cc      | 7 ++++---
 util/m5/src/command/checkpoint.cc     | 6 +++---
 util/m5/src/command/dumpresetstats.cc | 7 ++++---
 util/m5/src/command/dumpstats.cc      | 7 ++++---
 util/m5/src/command/exit.cc           | 7 ++++---
 util/m5/src/command/fail.cc           | 7 ++++---
 util/m5/src/command/initparam.cc      | 8 +++++---
 util/m5/src/command/loadsymbol.cc     | 4 ++--
 util/m5/src/command/readfile.cc       | 7 ++++---
 util/m5/src/command/resetstats.cc     | 7 ++++---
 util/m5/src/command/sum.cc            | 7 ++++---
 util/m5/src/command/writefile.cc      | 5 +++--
 15 files changed, 51 insertions(+), 39 deletions(-)

diff --git a/util/m5/src/command.cc b/util/m5/src/command.cc
index d7dc03028..2527dc6ae 100644
--- a/util/m5/src/command.cc
+++ b/util/m5/src/command.cc
@@ -52,6 +52,5 @@ Command::run(const DispatchTable &dt, Args &args)
     if (num_args < cmd.minArgs || num_args > cmd.maxArgs)
         return false;
 
-    cmd.func(dt, args);
-    return true;
+    return cmd.func(dt, args);
 }
diff --git a/util/m5/src/command.hh b/util/m5/src/command.hh
index 8348d1116..7321d3973 100644
--- a/util/m5/src/command.hh
+++ b/util/m5/src/command.hh
@@ -46,7 +46,7 @@ class Command
     // The maximum number of arguments the command can handle.
     const int maxArgs;
 
-    using FuncType = void (*)(const DispatchTable &dt, Args &args);
+    using FuncType = bool (*)(const DispatchTable &dt, Args &args);
     // A function which processes command line arguments and passes them to
     // the underlying function through the dispatch table.
     FuncType func;
diff --git a/util/m5/src/command.test.cc b/util/m5/src/command.test.cc
index 342a42cd4..b29d648fd 100644
--- a/util/m5/src/command.test.cc
+++ b/util/m5/src/command.test.cc
@@ -40,18 +40,20 @@ class DispatchTable {};
 
 DispatchTable dt;
 
-void
+bool
 do_test1(const DispatchTable &dt, Args &args)
 {
     ran_test1 = true;
+    return true;
 }
 
 bool ran_test2 = false;
 
-void
+bool
 do_test2(const DispatchTable &dt, Args &args)
 {
     ran_test2 = true;
+    return true;
 }
 
 TEST(CommandTest, OneCommandNoArgs)
diff --git a/util/m5/src/command/addsymbol.cc b/util/m5/src/command/addsymbol.cc
index dfd20d7c9..0ebd6b29a 100644
--- a/util/m5/src/command/addsymbol.cc
+++ b/util/m5/src/command/addsymbol.cc
@@ -29,20 +29,21 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
 
-void
+bool
 do_add_symbol(const DispatchTable &dt, Args &args)
 {
     uint64_t addr;
     if (!args.pop(addr))
-        usage();
+        return false;
     const std::string &symbol = args.pop();
 
     (*dt.m5_add_symbol)(addr, symbol.c_str());
+
+    return true;
 }
 
 Command add_symbol = {
diff --git a/util/m5/src/command/checkpoint.cc b/util/m5/src/command/checkpoint.cc
index bd234a7ce..b16307cee 100644
--- a/util/m5/src/command/checkpoint.cc
+++ b/util/m5/src/command/checkpoint.cc
@@ -29,19 +29,19 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
 
-void
+bool
 do_checkpoint(const DispatchTable &dt, Args &args)
 {
     uint64_t ns_delay, ns_period;
     if (!args.pop(ns_delay, 0) || !args.pop(ns_period, 0))
-        usage();
+        return false;
 
     (*dt.m5_checkpoint)(ns_delay, ns_period);
+    return true;
 }
 
 Command checkpoint = {
diff --git a/util/m5/src/command/dumpresetstats.cc b/util/m5/src/command/dumpresetstats.cc
index e3a7cc60e..b5337afae 100644
--- a/util/m5/src/command/dumpresetstats.cc
+++ b/util/m5/src/command/dumpresetstats.cc
@@ -29,19 +29,20 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
 
-void
+bool
 do_dump_reset_stats(const DispatchTable &dt, Args &args)
 {
     uint64_t ns_delay, ns_period;
     if (!args.pop(ns_delay, 0) || !args.pop(ns_period, 0))
-        usage();
+        return false;
 
     (*dt.m5_dump_reset_stats)(ns_delay, ns_period);
+
+    return true;
 }
 
 Command dump_reset_stats = {
diff --git a/util/m5/src/command/dumpstats.cc b/util/m5/src/command/dumpstats.cc
index eef3b383c..106f822a1 100644
--- a/util/m5/src/command/dumpstats.cc
+++ b/util/m5/src/command/dumpstats.cc
@@ -29,19 +29,20 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
 
-void
+bool
 do_dump_stats(const DispatchTable &dt, Args &args)
 {
     uint64_t ns_delay, ns_period;
     if (!args.pop(ns_delay, 0) || !args.pop(ns_period, 0))
-        usage();
+        return false;
 
     (*dt.m5_dump_stats)(ns_delay, ns_period);
+
+    return true;
 }
 
 Command dump_stats = {
diff --git a/util/m5/src/command/exit.cc b/util/m5/src/command/exit.cc
index ea322ca02..4f8815c27 100644
--- a/util/m5/src/command/exit.cc
+++ b/util/m5/src/command/exit.cc
@@ -29,19 +29,20 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
 
-void
+bool
 do_exit(const DispatchTable &dt, Args &args)
 {
     uint64_t ns_delay;
     if (!args.pop(ns_delay, 0))
-        usage();
+        return false;
 
     (*dt.m5_exit)(ns_delay);
+
+    return true;
 }
 
 Command exit_cmd = {
diff --git a/util/m5/src/command/fail.cc b/util/m5/src/command/fail.cc
index db21979ca..c34571c5c 100644
--- a/util/m5/src/command/fail.cc
+++ b/util/m5/src/command/fail.cc
@@ -29,19 +29,20 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
 
-void
+bool
 do_fail(const DispatchTable &dt, Args &args)
 {
     uint64_t ns_delay, code;
     if (!args.pop(code) || !args.pop(ns_delay, 0))
-        usage();
+        return false;
 
     (*dt.m5_fail)(ns_delay, code);
+
+    return true;
 }
 
 Command fail_cmd = {
diff --git a/util/m5/src/command/initparam.cc b/util/m5/src/command/initparam.cc
index 3fe000c10..eb1fdff46 100644
--- a/util/m5/src/command/initparam.cc
+++ b/util/m5/src/command/initparam.cc
@@ -31,19 +31,21 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
 
-void
+bool
 do_initparam(const DispatchTable &dt, Args &args)
 {
     uint64_t key_str[2];
     if (!args.pop(key_str, 2))
-        usage();
+        return false;
+
     uint64_t val = (*dt.m5_init_param)(key_str[0], key_str[1]);
     std::cout << val;
+
+    return true;
 }
 
 Command init_param = {
diff --git a/util/m5/src/command/loadsymbol.cc b/util/m5/src/command/loadsymbol.cc
index c55ae9905..794e53b47 100644
--- a/util/m5/src/command/loadsymbol.cc
+++ b/util/m5/src/command/loadsymbol.cc
@@ -29,15 +29,15 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
 
-void
+bool
 do_loadsymbol(const DispatchTable &dt, Args &args)
 {
     (*dt.m5_load_symbol)();
+    return true;
 }
 
 Command load_symbol = {
diff --git a/util/m5/src/command/readfile.cc b/util/m5/src/command/readfile.cc
index 9295dfd95..92c39e25f 100644
--- a/util/m5/src/command/readfile.cc
+++ b/util/m5/src/command/readfile.cc
@@ -32,7 +32,6 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
@@ -62,13 +61,15 @@ read_file(const DispatchTable &dt, std::ostream &os)
     return offset;
 }
 
-void
+bool
 do_read_file(const DispatchTable &dt, Args &args)
 {
     if (args.size() > 0)
-        usage();
+        return false;
 
     read_file(dt, std::cout);
+
+    return true;
 }
 
 Command read_file_cmd = {
diff --git a/util/m5/src/command/resetstats.cc b/util/m5/src/command/resetstats.cc
index 2408fb334..cf51bfb5a 100644
--- a/util/m5/src/command/resetstats.cc
+++ b/util/m5/src/command/resetstats.cc
@@ -29,19 +29,20 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
 
-void
+bool
 do_reset_stats(const DispatchTable &dt, Args &args)
 {
     uint64_t ns_delay, ns_period;
     if (!args.pop(ns_delay, 0) || !args.pop(ns_period, 0))
-        usage();
+        return false;
 
     (*dt.m5_reset_stats)(ns_delay, ns_period);
+
+    return true;
 }
 
 Command reset_stats = {
diff --git a/util/m5/src/command/sum.cc b/util/m5/src/command/sum.cc
index c7d44b397..8b1b3d276 100644
--- a/util/m5/src/command/sum.cc
+++ b/util/m5/src/command/sum.cc
@@ -31,22 +31,23 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
 
 // For testing purposes.
-void
+bool
 do_sum(const DispatchTable &dt, Args &args)
 {
     uint64_t a, b, c, d, e, f;
     if (!args.pop(a) || !args.pop(b) || !args.pop(c, 0) ||
             !args.pop(d, 0) || !args.pop(e, 0) || !args.pop(f, 0))
-        usage();
+        return false;
 
     unsigned sum = (*dt.m5_sum)(a, b, c, d, e, f);
     std::cout << "Sum is " << sum << "." << std::endl;
+
+    return true;
 }
 
 Command sum = {
diff --git a/util/m5/src/command/writefile.cc b/util/m5/src/command/writefile.cc
index 801b7af2a..bef193296 100644
--- a/util/m5/src/command/writefile.cc
+++ b/util/m5/src/command/writefile.cc
@@ -33,7 +33,6 @@
 #include "args.hh"
 #include "command.hh"
 #include "dispatch_table.hh"
-#include "usage.hh"
 
 namespace
 {
@@ -75,13 +74,15 @@ write_file(const DispatchTable &dt, const std::string &filename,
     std::cerr << "Wrote " << offset << " bytes." << std::endl;
 }
 
-void
+bool
 do_write_file(const DispatchTable &dt, Args &args)
 {
     const std::string &filename = args.pop();
     const std::string &host_filename = args.pop(filename);
 
     write_file(dt, filename, host_filename);
+
+    return true;
 }
 
 Command write_file_cmd = {
-- 
2.30.2