/*****************************************************************************/
/*                                                                           */
/*                                  main.c                                   */
/*                                                                           */
/*                     Main program for the ld65 linker                      */
/*                                                                           */
/*                                                                           */
/*                                                                           */
/* (C) 1998-2013, Ullrich von Bassewitz                                      */
/*                Roemerstrasse 52                                           */
/*                D-70794 Filderstadt                                        */
/* EMail:         uz@cc65.org                                                */
/*                                                                           */
/*                                                                           */
/* This software is provided 'as-is', without any expressed or implied       */
/* warranty.  In no event will the authors be held liable for any damages    */
/* arising from the use of this software.                                    */
/*                                                                           */
/* Permission is granted to anyone to use this software for any purpose,     */
/* including commercial applications, and to alter it and redistribute it    */
/* freely, subject to the following restrictions:                            */
/*                                                                           */
/* 1. The origin of this software must not be misrepresented; you must not   */
/*    claim that you wrote the original software. If you use this software   */
/*    in a product, an acknowledgment in the product documentation would be  */
/*    appreciated but is not required.                                       */
/* 2. Altered source versions must be plainly marked as such, and must not   */
/*    be misrepresented as being the original software.                      */
/* 3. This notice may not be removed or altered from any source              */
/*    distribution.                                                          */
/*                                                                           */
/*****************************************************************************/



#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

/* common */
#include "addrsize.h"
#include "chartype.h"
#include "cmdline.h"
#include "filetype.h"
#include "libdefs.h"
#include "objdefs.h"
#include "print.h"
#include "target.h"
#include "version.h"
#include "xmalloc.h"

/* ld65 */
#include "asserts.h"
#include "binfmt.h"
#include "condes.h"
#include "config.h"
#include "dbgfile.h"
#include "error.h"
#include "exports.h"
#include "fileio.h"
#include "filepath.h"
#include "global.h"
#include "library.h"
#include "mapfile.h"
#include "objfile.h"
#include "scanner.h"
#include "segments.h"
#include "spool.h"
#include "tpool.h"



/*****************************************************************************/
/*                                   Data                                    */
/*****************************************************************************/



static unsigned         ObjFiles   = 0; /* Count of object files linked */
static unsigned         LibFiles   = 0; /* Count of library files linked */

/* struct InputFile.Type definitions */
#define INPUT_FILES_FILE       0        /* Entry is a file (unknown type) */
#define INPUT_FILES_FILE_OBJ   1        /* Entry is a object file */
#define INPUT_FILES_FILE_LIB   2        /* Entry is a library file */
#define INPUT_FILES_SGROUP     3        /* Entry is 'StartGroup' */
#define INPUT_FILES_EGROUP     4        /* Entry is 'EndGroup' */

#define MAX_INPUTFILES         256

/* Array of inputs (libraries and object files) */
static struct InputFile {
    const char *FileName;
    unsigned Type;
}                              *InputFiles;
static unsigned                InputFilesCount = 0;
static const char              *CmdlineCfgFile = NULL,
                               *CmdlineTarget = NULL;



/*****************************************************************************/
/*                                   Code                                    */
/*****************************************************************************/



static void Usage (void)
/* Print usage information and exit */
{
    printf ("Usage: %s [options] module ...\n"
            "Short options:\n"
            "  -(\t\t\tStart a library group\n"
            "  -)\t\t\tEnd a library group\n"
            "  -C name\t\tUse linker config file\n"
            "  -D sym=val\t\tDefine a symbol\n"
            "  -L path\t\tSpecify a library search path\n"
            "  -Ln name\t\tCreate a VICE label file\n"
            "  -S addr\t\tSet the default start address\n"
            "  -V\t\t\tPrint the linker version\n"
            "  -h\t\t\tHelp (this text)\n"
            "  -m name\t\tCreate a map file\n"
            "  -o name\t\tName the default output file\n"
            "  -t sys\t\tSet the target system\n"
            "  -u sym\t\tForce an import of symbol 'sym'\n"
            "  -v\t\t\tVerbose mode\n"
            "  -vm\t\t\tVerbose map file\n"
            "\n"
            "Long options:\n"
            "  --allow-multiple-definition\tAllow multiple definitions\n"
            "  --cfg-path path\t\tSpecify a config file search path\n"
            "  --config name\t\t\tUse linker config file\n"
            "  --dbgfile name\t\tGenerate debug information\n"
            "  --define sym=val\t\tDefine a symbol\n"
            "  --end-group\t\t\tEnd a library group\n"
            "  --force-import sym\t\tForce an import of symbol 'sym'\n"
            "  --help\t\t\tHelp (this text)\n"
            "  --large-alignment\t\tDon't warn about large alignments\n"
            "  --lib file\t\t\tLink this library\n"
            "  --lib-path path\t\tSpecify a library search path\n"
            "  --mapfile name\t\tCreate a map file\n"
            "  --module-id id\t\tSpecify a module id\n"
            "  --obj file\t\t\tLink this object file\n"
            "  --obj-path path\t\tSpecify an object file search path\n"
            "  --start-addr addr\t\tSet the default start address\n"
            "  --start-group\t\t\tStart a library group\n"
            "  --target sys\t\t\tSet the target system\n"
            "  --version\t\t\tPrint the linker version\n",
            ProgName);
}



static unsigned long CvtNumber (const char* Arg, const char* Number)
/* Convert a number from a string. Allow '$' and '0x' prefixes for hex
** numbers.
*/
{
    unsigned long Val;
    int           Converted;

    /* Convert */
    if (*Number == '$') {
        ++Number;
        Converted = sscanf (Number, "%lx", &Val);
    } else {
        Converted = sscanf (Number, "%li", (long*)&Val);
    }

    /* Check if we do really have a number */
    if (Converted != 1) {
        Error ("Invalid number given in argument: %s\n", Arg);
    }

    /* Return the result */
    return Val;
}



static void LinkFile (const char* Name, FILETYPE Type)
/* Handle one file */
{
    char*         PathName;
    FILE*         F;
    unsigned long Magic;


    /* If we don't know the file type, determine it from the extension */
    if (Type == FILETYPE_UNKNOWN) {
        Type = GetFileType (Name);
    }

    /* For known file types, search the file in the directory list */
    switch (Type) {

        case FILETYPE_LIB:
            PathName = SearchFile (LibSearchPath, Name);
            if (PathName == 0) {
                PathName = SearchFile (LibDefaultPath, Name);
            }
            break;

        case FILETYPE_OBJ:
            PathName = SearchFile (ObjSearchPath, Name);
            if (PathName == 0) {
                PathName = SearchFile (ObjDefaultPath, Name);
            }
            break;

        default:
            PathName = xstrdup (Name);   /* Use the name as is */
            break;
    }

    /* We must have a valid name now */
    if (PathName == 0) {
        Error ("Input file '%s' not found", Name);
    }

    /* Try to open the file */
    F = fopen (PathName, "rb");
    if (F == 0) {
        Error ("Cannot open '%s': %s", PathName, strerror (errno));
    }

    /* Read the magic word */
    Magic = Read32 (F);

    /* Check the magic for known file types. The handling is somewhat weird
    ** since we may have given a file with a ".lib" extension, which was
    ** searched and found in a directory for library files, but we now find
    ** out (by looking at the magic) that it's indeed an object file. We just
    ** ignore the problem and hope no one will notice...
    */
    switch (Magic) {

        case OBJ_MAGIC:
            ObjAdd (F, PathName);
            ++ObjFiles;
            break;

        case LIB_MAGIC:
            LibAdd (F, PathName);
            ++LibFiles;
            break;

        default:
            fclose (F);
            Error ("File '%s' has unknown type", PathName);

    }

    /* Free allocated memory. */
    xfree (PathName);
}



static void DefineSymbol (const char* Def)
/* Define a symbol from the command line */
{
    const char* P;
    long Val;
    StrBuf SymName = AUTO_STRBUF_INITIALIZER;


    /* The symbol must start with a character or underline */
    if (Def [0] != '_' && !IsAlpha (Def [0])) {
        InvDef (Def);
    }
    P = Def;

    /* Copy the symbol, checking the remainder */
    while (IsAlNum (*P) || *P == '_') {
        SB_AppendChar (&SymName, *P++);
    }
    SB_Terminate (&SymName);

    /* Do we have a value given? */
    if (*P != '=') {
        InvDef (Def);
    } else {
        /* We have a value */
        ++P;
        if (*P == '$') {
            ++P;
            if (sscanf (P, "%lx", &Val) != 1) {
                InvDef (Def);
            }
        } else {
            if (sscanf (P, "%li", &Val) != 1) {
                InvDef (Def);
            }
        }
    }

    /* Define the new symbol */
    CreateConstExport (GetStringId (SB_GetConstBuf (&SymName)), Val);
}



static void OptCfgPath (const char* Opt attribute ((unused)), const char* Arg)
/* Specify a config file search path */
{
    AddSearchPath (CfgSearchPath, Arg);
}



static void OptConfig (const char* Opt attribute ((unused)), const char* Arg)
/* Define the config file */
{
    char* PathName;

    if (CfgAvail ()) {
        Error ("Cannot use -C/-t twice");
    }
    /* Search for the file */
    PathName = SearchFile (CfgSearchPath, Arg);
    if (PathName == 0) {
        PathName = SearchFile (CfgDefaultPath, Arg);
    }
    if (PathName == 0) {
        Error ("Cannot find config file '%s'", Arg);
    }

    /* Read the config */
    CfgSetName (PathName);
    CfgRead ();
}



static void OptDbgFile (const char* Opt attribute ((unused)), const char* Arg)
/* Give the name of the debug file */
{
    DbgFileName = Arg;
}



static void OptDefine (const char* Opt attribute ((unused)), const char* Arg)
/* Define a symbol on the command line */
{
    DefineSymbol (Arg);
}



static void OptEndGroup (const char* Opt attribute ((unused)),
                         const char* Arg attribute ((unused)))
/* End a library group */
{
    LibEndGroup ();
}



static void OptForceImport (const char* Opt attribute ((unused)), const char* Arg)
/* Force an import of a symbol */
{
    /* An optional address size may be specified */
    const char* ColPos = strchr (Arg, ':');
    if (ColPos == 0) {

        /* Use default address size (which for now is always absolute
        ** addressing)
        */
        InsertImport (GenImport (GetStringId (Arg), ADDR_SIZE_ABS));

    } else {

        char* A;

        /* Get the address size and check it */
        unsigned char AddrSize = AddrSizeFromStr (ColPos+1);
        if (AddrSize == ADDR_SIZE_INVALID) {
            Error ("Invalid address size '%s'", ColPos+1);
        }

        /* Create a copy of the argument */
        A = xstrdup (Arg);

        /* We need just the symbol */
        A[ColPos - Arg] = '\0';

        /* Generate the import */
        InsertImport (GenImport (GetStringId (A), AddrSize));

        /* Delete the copy of the argument */
        xfree (A);
    }
}



static void OptHelp (const char* Opt attribute ((unused)),
                     const char* Arg attribute ((unused)))
/* Print usage information and exit */
{
    Usage ();
    exit (EXIT_SUCCESS);
}



static void OptLargeAlignment (const char* Opt attribute ((unused)),
                               const char* Arg attribute ((unused)))
/* Don't warn about large alignments */
{
    LargeAlignment = 1;
}


static void OptLib (const char* Opt attribute ((unused)), const char* Arg)
/* Link a library */
{
    InputFiles[InputFilesCount].Type = INPUT_FILES_FILE_LIB;
    InputFiles[InputFilesCount].FileName = Arg;
    if (++InputFilesCount >= MAX_INPUTFILES)
        Error ("Too many input files");
}



static void OptLibPath (const char* Opt attribute ((unused)), const char* Arg)
/* Specify a library file search path */
{
    AddSearchPath (LibSearchPath, Arg);
}



static void OptMapFile (const char* Opt attribute ((unused)), const char* Arg)
/* Give the name of the map file */
{
    if (MapFileName) {
        Error ("Cannot use -m twice");
    }
    MapFileName = Arg;
}



static void OptModuleId (const char* Opt, const char* Arg)
/* Specify a module id */
{
    unsigned long Id = CvtNumber (Opt, Arg);
    if (Id > 0xFFFFUL) {
        Error ("Range error in module id");
    }
    ModuleId = (unsigned) Id;
}



static void OptObj (const char* Opt attribute ((unused)), const char* Arg)
/* Link an object file */
{
    InputFiles[InputFilesCount].Type = INPUT_FILES_FILE_OBJ;
    InputFiles[InputFilesCount].FileName = Arg;
    if (++InputFilesCount >= MAX_INPUTFILES)
        Error ("Too many input files");
}



static void OptObjPath (const char* Opt attribute ((unused)), const char* Arg)
/* Specify an object file search path */
{
    AddSearchPath (ObjSearchPath, Arg);
}



static void OptOutputName (const char* Opt attribute ((unused)), const char* Arg)
/* Give the name of the output file */
{
    static int OutputNameSeen = 0;
    if (OutputNameSeen) {
        Error ("Cannot use -o twice");
    }
    OutputNameSeen = 1;
    OutputName = Arg;
}



static void OptStartAddr (const char* Opt, const char* Arg)
/* Set the default start address */
{
    if (HaveStartAddr) {
        Error ("Cannot use -S twice");
    }
    StartAddr = CvtNumber (Opt, Arg);
    HaveStartAddr = 1;
}



static void OptStartGroup (const char* Opt attribute ((unused)),
                           const char* Arg attribute ((unused)))
/* Start a library group */
{
    LibStartGroup ();
}



static void OptTarget (const char* Opt attribute ((unused)), const char* Arg)
/* Set the target system */
{
    StrBuf FileName = STATIC_STRBUF_INITIALIZER;
    char*  PathName;

    /* Map the target name to a target id */
    Target = FindTarget (Arg);
    if (Target == TGT_UNKNOWN) {
        Error ("Invalid target name: '%s'", Arg);
    }

    /* Set the target binary format */
    DefaultBinFmt = GetTargetProperties (Target)->BinFmt;

    /* Build config file name from target name */
    SB_CopyStr (&FileName, GetTargetName (Target));
    SB_AppendStr (&FileName, ".cfg");
    SB_Terminate (&FileName);

    /* Search for the file */
    PathName = SearchFile (CfgSearchPath, SB_GetBuf (&FileName));
    if (PathName == 0) {
        PathName = SearchFile (CfgDefaultPath, SB_GetBuf (&FileName));
    }
    if (PathName == 0) {
        Error ("Cannot find config file '%s'", SB_GetBuf (&FileName));
    }

    /* Free file name memory */
    SB_Done (&FileName);

    /* Read the file */
    CfgSetName (PathName);
    CfgRead ();
}



static void OptVersion (const char* Opt attribute ((unused)),
                        const char* Arg attribute ((unused)))
/* Print the assembler version */
{
    fprintf (stderr, "%s V%s\n", ProgName, GetVersionAsString ());
    exit(EXIT_SUCCESS);
}



static void OptMultDef (const char* Opt attribute ((unused)),
                        const char* Arg attribute ((unused)))
/* Set flag to allow multiple definitions of a global symbol */
{
    AllowMultDef = 1;
}



static void CmdlOptStartGroup (const char* Opt attribute ((unused)),
                               const char* Arg attribute ((unused)))
/* Remember 'start group' occurrence in input files array */
{
    InputFiles[InputFilesCount].Type = INPUT_FILES_SGROUP;
    InputFiles[InputFilesCount].FileName = Arg;  /* Unused */
    if (++InputFilesCount >= MAX_INPUTFILES)
        Error ("Too many input files");
}



static void CmdlOptEndGroup (const char* Opt attribute ((unused)),
                             const char* Arg attribute ((unused)))
/* Remember 'end group' occurrence in input files array */
{
    InputFiles[InputFilesCount].Type = INPUT_FILES_EGROUP;
    InputFiles[InputFilesCount].FileName = Arg;  /* Unused */
    if (++InputFilesCount >= MAX_INPUTFILES)
        Error ("Too many input files");
}



static void CmdlOptConfig (const char* Opt attribute ((unused)), const char* Arg)
/* Set 'config file' command line parameter */
{
    if (CmdlineCfgFile || CmdlineTarget) {
        Error ("Cannot use -C/-t twice");
    }
    CmdlineCfgFile = Arg;
}



static void CmdlOptTarget (const char* Opt attribute ((unused)), const char* Arg)
/* Set 'target' command line parameter */
{
    if (CmdlineCfgFile || CmdlineTarget) {
        Error ("Cannot use -C/-t twice");
    }
    CmdlineTarget = Arg;
}



static void ParseCommandLine(void)
{
    /* Program long options */
    static const LongOpt OptTab[] = {
        { "--allow-multiple-definition", 0,      OptMultDef              },
        { "--cfg-path",                  1,      OptCfgPath              },
        { "--config",                    1,      CmdlOptConfig           },
        { "--dbgfile",                   1,      OptDbgFile              },
        { "--define",                    1,      OptDefine               },
        { "--end-group",                 0,      CmdlOptEndGroup         },
        { "--force-import",              1,      OptForceImport          },
        { "--help",                      0,      OptHelp                 },
        { "--large-alignment",           0,      OptLargeAlignment       },
        { "--lib",                       1,      OptLib                  },
        { "--lib-path",                  1,      OptLibPath              },
        { "--mapfile",                   1,      OptMapFile              },
        { "--module-id",                 1,      OptModuleId             },
        { "--obj",                       1,      OptObj                  },
        { "--obj-path",                  1,      OptObjPath              },
        { "--start-addr",                1,      OptStartAddr            },
        { "--start-group",               0,      CmdlOptStartGroup       },
        { "--target",                    1,      CmdlOptTarget           },
        { "--version",                   0,      OptVersion              },
    };

    unsigned I;
    unsigned LabelFileGiven = 0;

    /* Allocate memory for input file array */
    InputFiles = xmalloc (MAX_INPUTFILES * sizeof (struct InputFile));

    /* Defer setting of config/target and input files until all options are parsed */
    I = 1;
    while (I < ArgCount) {

        /* Get the argument */
        const char* Arg = ArgVec[I];

        /* Check for an option */
        if (Arg [0] == '-') {

            /* An option */
            switch (Arg [1]) {

                case '-':
                    LongOption (&I, OptTab, sizeof(OptTab)/sizeof(OptTab[0]));
                    break;

                case '(':
                    CmdlOptStartGroup (Arg, 0);
                    break;

                case ')':
                    CmdlOptEndGroup (Arg, 0);
                    break;

                case 'h':
                case '?':
                    OptHelp (Arg, 0);
                    break;

                case 'm':
                    OptMapFile (Arg, GetArg (&I, 2));
                    break;

                case 'o':
                    OptOutputName (NULL, GetArg (&I, 2));
                    break;

                case 't':
                    CmdlOptTarget (Arg, GetArg (&I, 2));
                    break;

                case 'u':
                    OptForceImport (Arg, GetArg (&I, 2));
                    break;

                case 'v':
                    switch (Arg [2]) {
                        case 'm':   VerboseMap = 1;     break;
                        case '\0':  ++Verbosity;        break;
                        default:    UnknownOption (Arg);
                    }
                    break;

                case 'C':
                    CmdlOptConfig (Arg, GetArg (&I, 2));
                    break;

                case 'D':
                    OptDefine (Arg, GetArg (&I, 2));
                    break;

                case 'L':
                    switch (Arg [2]) {
                        case 'n':
                            /* ## This one is obsolete and will go */
                            if (LabelFileGiven) {
                                Error ("Cannot use -Ln twice");
                            }
                            LabelFileGiven = 1;
                            LabelFileName = GetArg (&I, 3);
                            break;
                        default:
                            OptLibPath (Arg, GetArg (&I, 2));
                            break;
                    }
                    break;

                case 'S':
                    OptStartAddr (Arg, GetArg (&I, 2));
                    break;

                case 'V':
                    OptVersion (Arg, 0);
                    break;

                default:
                    UnknownOption (Arg);
                    break;
            }

        } else {

            /* A filename */
            InputFiles[InputFilesCount].Type = INPUT_FILES_FILE;
            InputFiles[InputFilesCount].FileName = Arg;
            if (++InputFilesCount >= MAX_INPUTFILES)
                Error ("Too many input files");

        }

        /* Next argument */
        ++I;
    }

    if (CmdlineTarget) {
        OptTarget (NULL, CmdlineTarget);
    } else if (CmdlineCfgFile) {
        OptConfig (NULL, CmdlineCfgFile);
    }

    /* Process input files */
    for (I = 0; I < InputFilesCount; ++I) {
        switch (InputFiles[I].Type) {
            case INPUT_FILES_FILE:
                LinkFile (InputFiles[I].FileName, FILETYPE_UNKNOWN);
                break;
            case INPUT_FILES_FILE_LIB:
                LinkFile (InputFiles[I].FileName, FILETYPE_LIB);
                break;
            case INPUT_FILES_FILE_OBJ:
                LinkFile (InputFiles[I].FileName, FILETYPE_OBJ);
                break;
            case INPUT_FILES_SGROUP:
                OptStartGroup (NULL, 0);
                break;
            case INPUT_FILES_EGROUP:
                OptEndGroup (NULL, 0);
                break;
            default:
                abort ();
        }
    }

    /* Free memory used for input file array */
    xfree (InputFiles);
}



int main (int argc, char* argv [])
/* Linker main program */
{
    unsigned MemoryAreaOverflows;

    /* Initialize the cmdline module */
    InitCmdLine (&argc, &argv, "ld65");

    /* Initialize the input file search paths */
    InitSearchPaths ();

    /* Initialize the string pool */
    InitStrPool ();

    /* Initialize the type pool */
    InitTypePool ();

    /* Parse the command line */
    ParseCommandLine ();

    /* Check if we had any object files */
    if (ObjFiles == 0) {
        Error ("No object files to link");
    }

    /* Check if we have a valid configuration */
    if (!CfgAvail ()) {
        Error ("Memory configuration missing");
    }

    /* Check if we have open library groups */
    LibCheckGroup ();

    /* Create the condes tables if requested */
    ConDesCreate ();

    /* Process data from the config file. Assign start addresses for the
    ** segments, define linker symbols. The function will return the number
    ** of memory area overflows (zero on success).
    */
    MemoryAreaOverflows = CfgProcess ();

    /* Check module assertions */
    CheckAssertions ();

    /* Check for import/export mismatches */
    CheckExports ();

    /* If we had a memory area overflow before, we cannot generate the output
    ** file. However, we will generate a short map file if requested, since
    ** this will help the user to rearrange segments and fix the overflow.
    */
    if (MemoryAreaOverflows) {
        if (MapFileName) {
            CreateMapFile (SHORT_MAPFILE);
        }
        Error ("Cannot generate most of the files due to memory area overflow%c",
               (MemoryAreaOverflows > 1) ? 's' : ' ');
    }

    /* Create the output file */
    CfgWriteTarget ();

    /* Check for segments not written to the output file */
    CheckSegments ();

    /* If requested, create a map file and a label file for VICE */
    if (MapFileName) {
        CreateMapFile (LONG_MAPFILE);
    }
    if (LabelFileName) {
        CreateLabelFile ();
    }
    if (DbgFileName) {
        CreateDbgFile ();
    }

    /* Dump the data for debugging */
    if (Verbosity > 1) {
        SegDump ();
        ConDesDump ();
    }

    /* Return an apropriate exit code */
    return EXIT_SUCCESS;
}