From ea1b208c33295f0b81f369bcb638a73c5a83c439 Mon Sep 17 00:00:00 2001
From: Michael Davidsaver <mdavidsaver@gmail.com>
Date: Mon, 24 Jun 2019 13:23:28 -0700
Subject: [PATCH] redo softIoc to be more c++y

---
 modules/database/src/std/softIoc/softMain.cpp | 419 ++++++++----------
 1 file changed, 197 insertions(+), 222 deletions(-)

diff --git a/modules/database/src/std/softIoc/softMain.cpp b/modules/database/src/std/softIoc/softMain.cpp
index 01ef19b2f..bc945c80e 100644
--- a/modules/database/src/std/softIoc/softMain.cpp
+++ b/modules/database/src/std/softIoc/softMain.cpp
@@ -9,55 +9,12 @@
 
 /* Author: Andrew Johnson	Date: 2003-04-08 */
 
-/* Usage:
- *  softIoc [-D softIoc.dbd] [-h] [-S] [-s] [-a ascf]
- *	[-m macro=value,macro2=value2] [-d file.db]
- *	[-x prefix] [st.cmd]
- *
- *  If used the -D option must come first, and specify the
- *  path to the softIoc.dbd file.  The compile-time install
- *  location is saved in the binary as a default.
- *
- *  Usage information will be printed if -h is given, then
- *  the program will exit normally.
- *
- *  The -S option prevents an interactive shell being started
- *  after all arguments have been processed.
- *
- *  Previous versions accepted a -s option to cause a shell
- *  to be started; this option is still accepted but ignored
- *  since a command shell is now started by default.
- *
- *  Access Security can be enabled with the -a option giving
- *  the name of the configuration file; if any macros were
- *  set with -m before the -a option was given, they will be
- *  used as access security substitution macros.
- *
- *  Any number of -m and -d arguments can be interspersed;
- *  the macros are applied to the following .db files.  Each
- *  later -m option causes earlier macros to be discarded.
- *
- *  The -x option loads the softIocExit.db with the macro
- *  IOC set to the string provided.  This database contains
- *  a subroutine record named $(IOC):exit which has its field
- *  SNAM set to "exit".  When this record is processed, the
- *  subroutine that runs will call epicsExit() with the value
- *  of the field A determining whether the exit status is
- *  EXIT_SUCCESS if (A == 0.0) or EXIT_FAILURE (A != 0.0).
- *
- *  A st.cmd file is optional.  If any databases were loaded
- *  the st.cmd file will be run *after* iocInit.  To perform
- *  iocsh commands before iocInit, all database loading must
- *  be performed by the script itself, or by the user from
- *  the interactive IOC shell.
- */
-
-#include <stddef.h>
-#include <stdlib.h>
-#include <stddef.h>
-#include <string.h>
-#include <stdio.h>
+#include <iostream>
+#include <string>
+#include <list>
+#include <stdexcept>
 
+#include <epicsGetopt.h>
 #include "registryFunction.h"
 #include "epicsThread.h"
 #include "epicsExit.h"
@@ -74,6 +31,12 @@
 
 extern "C" int softIoc_registerRecordDeviceDriver(struct dbBase *pdbbase);
 
+#ifndef EPICS_BASE
+// so IDEs knows EPICS_BASE is a string constant
+#  define EPICS_BASE "/"
+#  error -DEPICS_BASE required
+#endif
+
 #define DBD_BASE "dbd/softIoc.dbd"
 #define EXIT_BASE "db/softIocExit.db"
 #define DBD_FILE_REL "../../" DBD_BASE
@@ -81,190 +44,202 @@ extern "C" int softIoc_registerRecordDeviceDriver(struct dbBase *pdbbase);
 #define DBD_FILE EPICS_BASE "/" DBD_BASE
 #define EXIT_FILE EPICS_BASE "/" EXIT_BASE
 
-const char *arg0;
-const char *base_dbd = DBD_FILE;
-const char *exit_db = EXIT_FILE;
-
-static void preparePath(void)
-{
-    FILE *fp;
-    char *prefix = epicsGetExecDir();
-    char *dbd, *exit;
-    if(!prefix) return;
-
-    dbd = (char*)malloc(strlen(prefix) + strlen(DBD_FILE_REL) + 1);
-    if(dbd) {
-        dbd[0] = '\0';
-        strcat(dbd, prefix);
-        strcat(dbd, DBD_FILE_REL);
-        printf("Testing '%s'\n", dbd);
-        if((fp = fopen(dbd, "rb"))!=NULL) {
-            fclose(fp);
-            base_dbd = dbd;
-        }
-    }
-
-    exit = (char*)malloc(strlen(prefix) + strlen(EXIT_FILE_REL) + 1);
-    if(exit) {
-        exit[0] = '\0';
-        strcat(exit, prefix);
-        strcat(exit, EXIT_FILE_REL);
-        if((fp = fopen(exit, "rb"))!=NULL) {
-            fclose(fp);
-            exit_db = exit;
-        }
-    }
-}
+namespace {
 
 static void exitSubroutine(subRecord *precord) {
     epicsExitLater((precord->a == 0.0) ? EXIT_SUCCESS : EXIT_FAILURE);
 }
 
-static void usage(int status) {
-    printf("Usage: %s [-D softIoc.dbd] [-h] [-S] [-a ascf]\n", arg0);
-    puts("\t[-m macro=value,macro2=value2] [-d file.db]");
-    puts("\t[-x prefix] [st.cmd]");
-    puts("Compiled-in path to softIoc.dbd is:");
-    printf("\t%s\n", base_dbd);
-    epicsExit(status);
+void usage(const char *arg0, const std::string& base_dbd) {
+    std::cout<<"Usage: "<<arg0<<
+               " [-D softIoc.dbd] [-h] [-S] [-s] [-a ascf]\n"
+               "[-m macro=value,macro2=value2] [-d file.db]\n"
+               "[-x prefix] [st.cmd]\n"
+               "\n"
+               "    -D <dbd>  If used, must come first. Specify the path to the softIoc.dbdfile."
+               "        The compile-time install location is saved in the binary as a default.\n"
+               "\n"
+               "    -h  Print this mesage and exit.\n"
+               "\n"
+               "    -S  Prevents an interactive shell being started.\n"
+               "\n"
+               "    -s  Previously caused a shell to be started.  Now accepted and ignored.\n"
+               "\n"
+               "    -a <acf>  Access Security configuration file.  Macro substitution is\n"
+               "        performed.\n"
+               "\n"
+               "    -m <MAC>=<value>,... Set/replace macro definitions used by subsequent -d and\n"
+               "        -a.\n"
+               "\n"
+               "    -d <db>  Load records from file (dbLoadRecords).  Macro substitution is\n"
+               "        performed.\n"
+               "\n"
+               "    -x <prefix>  Load softIocExit.db.  Provides a record \"<prefix>:exit\".\n"
+               "        Put 0 to exit with success, or non-zero to exit with an error.\n"
+               "\n"
+               "Any number of -m and -d arguments can be interspersed; the macros are applied\n"
+               "to the following .db files.  Each later -m option causes earlier macros to be\n"
+               "discarded.\n"
+               "\n"
+               "A st.cmd file is optional.  If any databases were loaded the st.cmd file will\n"
+               "be run *after* iocInit.  To perform iocsh commands before iocInit, all database\n"
+               "loading must be performed by the script itself, or by the user from the\n"
+               "interactive IOC shell.\n"
+               "\n"
+               "Compiled-in path to softIoc.dbd is:\n"
+               "\t"<<base_dbd.c_str()<<"\n";
 }
 
+void errIf(int ret, const std::string& msg)
+{
+    if(ret)
+        throw std::runtime_error(msg);
+}
+
+void lazy_dbd(const std::string& dbd_file) {
+    static bool loaded;
+    if(loaded) return;
+    loaded = true;
+
+    errIf(dbLoadDatabase(dbd_file.c_str(), NULL, NULL),
+          std::string("Failed to load DBD file: ")+dbd_file);
+    std::cout<<"dbLoadDatabase(\""<<dbd_file<<"\")\n";
+
+    softIoc_registerRecordDeviceDriver(pdbbase);
+    std::cout<<"softIoc_registerRecordDeviceDriver(pdbbase)\n";
+    registryFunctionAdd("exit", (REGISTRYFUNCTION) exitSubroutine);
+}
+
+} // namespace
 
 int main(int argc, char *argv[])
 {
-    preparePath();
-    char *dbd_file = const_cast<char*>(base_dbd);
-    char *macros = NULL;
-    char xmacro[PVNAME_STRINGSZ + 4];
-    int startIocsh = 1;	/* default = start shell */
-    int loadedDb = 0;
-    
-    arg0 = strrchr(*argv, '/');
-    if (!arg0) {
-	arg0 = *argv;
-    } else {
-	++arg0;	/* skip the '/' */
-    }
-    
-    --argc, ++argv;
-    
-    /* Do this here in case the dbd file not available */
-    if (argc>0 && **argv=='-' && (*argv)[1]=='h') {
-	usage(EXIT_SUCCESS);
-    }
-    
-    if (argc>1 && **argv=='-' && (*argv)[1]=='D') {
-	dbd_file = *++argv;
-	argc -= 2;
-	++argv;
-    }
-    
-    if (dbLoadDatabase(dbd_file, NULL, NULL)) {
-	epicsExit(EXIT_FAILURE);
-    }
-    
-    softIoc_registerRecordDeviceDriver(pdbbase);
-    registryFunctionAdd("exit", (REGISTRYFUNCTION) exitSubroutine);
+    try {
+        std::string dbd_file(DBD_FILE),
+                    exit_file(EXIT_FILE),
+                    macros, // scratch space for macros (may be given more than once)
+                    xmacro;
+        bool interactive = true;
+        bool loadedDb = false;
 
-    while (argc>1 && **argv == '-') {
-	switch ((*argv)[1]) {
-	case 'a':
-	    if (macros) asSetSubstitutions(macros);
-	    asSetFilename(*++argv);
-	    --argc;
-	    break;
-	
-	case 'd':
-	    if (dbLoadRecords(*++argv, macros)) {
-		epicsExit(EXIT_FAILURE);
-	    }
-	    loadedDb = 1;
-	    --argc;
-	    break;
-	
-	case 'h':
-	    usage(EXIT_SUCCESS);
-	
-	case 'm':
-	    macros = *++argv;
-	    --argc;
-	    break;
-	
-	case 'S':
-	    startIocsh = 0;
-	    break;
-	
-	case 's':
-	    break;
-	
-	case 'x':
-	    epicsSnprintf(xmacro, sizeof xmacro, "IOC=%s", *++argv);
-	    if (dbLoadRecords(exit_db, xmacro)) {
-		epicsExit(EXIT_FAILURE);
-	    }
-	    loadedDb = 1;
-	    --argc;
-	    break;
-	
-	default:
-	    printf("%s: option '%s' not recognized\n", arg0, *argv);
-	    usage(EXIT_FAILURE);
-	}
-	--argc;
-	++argv;
+        // attempt to compute relative paths
+        {
+            std::string prefix;
+            char *cprefix = epicsGetExecDir();
+            if(cprefix) {
+                try {
+                    prefix = cprefix;
+                    free(cprefix);
+                } catch(...) {
+                    free(cprefix);
+                    throw;
+                }
+            }
+
+            dbd_file = prefix + DBD_FILE_REL;
+            exit_file = prefix + EXIT_FILE_REL;
+        }
+
+        int opt;
+
+        while ((opt = getopt(argc, argv, "ha:d:m:Ssx:")) != -1) {
+            switch (opt) {
+            case 'h':               /* Print usage */
+                usage(argv[0], dbd_file);
+                epicsExit(0);
+                return 0;
+            default:
+                usage(argv[0], dbd_file);
+                std::cerr<<"Unknown argument: -"<<char(opt)<<"\n";
+                epicsExit(2);
+                return 2;
+            case 'a':
+                lazy_dbd(dbd_file);
+                if (!macros.empty()) {
+                    if(asSetSubstitutions(macros.c_str()))
+                        throw std::bad_alloc();
+                    std::cout<<"asSetSubstitutions(\""<<macros<<"\")\n";
+                }
+                if(asSetFilename(optarg))
+                    throw std::bad_alloc();
+                std::cout<<"asSetFilename(\""<<optarg<<"\")\n";
+                break;
+            case 'd':
+                lazy_dbd(dbd_file);
+                errIf(dbLoadRecords(optarg, macros.c_str()),
+                      std::string("Failed to load: ")+optarg);
+                std::cout<<"dbLoadRecords(\""<<optarg<<"\"";
+                if(!macros.empty())
+                    std::cout<<", \""<<macros<<"\"";
+                std::cout<<")\n";
+                loadedDb = true;
+                break;
+            case 'm':
+                macros = optarg;
+                break;
+            case 'S':
+                interactive = false;
+                break;
+            case 's':
+                break; // historical
+            case 'x':
+                lazy_dbd(dbd_file);
+                xmacro  = "IOC=";
+                xmacro += optarg;
+                errIf(dbLoadRecords(exit_file.c_str(), xmacro.c_str()),
+                      std::string("Failed to load: ")+exit_file);
+                loadedDb = true;
+                break;
+            }
+        }
+
+        lazy_dbd(dbd_file);
+
+        if(optind<argc)  {
+            // run script
+            // ignore any extra positional args (historical)
+
+            std::cout<<"# Begin "<<argv[optind]<<"\n";
+            errIf(iocsh(argv[optind]),
+                        std::string("Error in ")+argv[optind]);
+            std::cout<<"# End "<<argv[optind]<<"\n";
+
+            epicsThreadSleep(0.2);
+            loadedDb = true;	/* Give it the benefit of the doubt... */
+        }
+
+        if (loadedDb) {
+            std::cout<<"iocInit()\n";
+            iocInit();
+            epicsThreadSleep(0.2);
+        }
+
+        if(interactive) {
+            std::cout.flush();
+            std::cerr.flush();
+            if(iocsh(NULL)) {
+                epicsExit(1);
+                return 1;
+            }
+
+        } else {
+            if (loadedDb) {
+                epicsThreadExitMain();
+
+            } else {
+                usage(argv[0], dbd_file);
+                std::cerr<<"Nothing to do!\n";
+                epicsExit(1);
+                return 1;
+            }
+        }
+
+        epicsExit(0);
+        return 0;
+
+    }catch(std::exception& e){
+        std::cerr<<"Error: "<<e.what()<<"\n";
+        epicsExit(2);
+        return 2;
     }
-    
-    if (argc>0 && **argv=='-') {
-	switch((*argv)[1]) {
-	case 'a':
-	case 'd':
-	case 'm':
-	case 'x':
-	    printf("%s: missing argument to option '%s'\n", arg0, *argv);
-	    usage(EXIT_FAILURE);
-	
-	case 'h':
-	    usage(EXIT_SUCCESS);
-	
-	case 'S':
-	    startIocsh = 0;
-	    break;
-	
-	case 's':
-	    break;
-	
-	default:
-	    printf("%s: option '%s' not recognized\n", arg0, *argv);
-	    usage(EXIT_FAILURE);
-	}
-	--argc;
-	++argv;
-    }
-    
-    if (loadedDb) {
-	iocInit();
-	epicsThreadSleep(0.2);
-    }
-    
-    /* run user's startup script */
-    if (argc>0) {
-	if (iocsh(*argv)) epicsExit(EXIT_FAILURE);
-	epicsThreadSleep(0.2);
-	loadedDb = 1;	/* Give it the benefit of the doubt... */
-    }
-    
-    /* start an interactive shell if it was requested */
-    if (startIocsh) {
-	iocsh(NULL);
-    } else {
-	if (loadedDb) {
-	    epicsThreadExitMain();
-	} else {
-	    printf("%s: Nothing to do!\n", arg0);
-	    usage(EXIT_FAILURE);
-	}
-    }
-    epicsExit(EXIT_SUCCESS);
-    /*Note that the following statement will never be executed*/
-    return 0;
 }