/*****************************************************************************
*   $Id: entry.c,v 7.1 1998/12/07 01:38:00 darren Exp $
*
*   Copyright (c) 1996-1998, Darren Hiebert
*
*   This source code is released for free distribution under the terms of the
*   GNU General Public License.
*
*   This module contains functions for creating tag entries.
*****************************************************************************/

/*============================================================================
=   Include files
============================================================================*/
#include "general.h"

#include <string.h>
#include <ctype.h>      /* to define isspace() */
#include <errno.h>

#if defined(HAVE_UNISTD_H)
# include <unistd.h>    /* to declare close(), ftruncate(), truncate() */
#endif

/*  These header files provide for the functions necessary to do file
 *  truncation.
 */
#include <fcntl.h>
#ifdef HAVE_IO_H
# include <io.h>
#endif

#include "debug.h"
#include "entry.h"
#include "main.h"
#include "options.h"
#include "read.h"

/*============================================================================
*=      Defines
============================================================================*/
#define PSEUDO_TAG_PREFIX       "!_"

#define includeExtensionFlags()         (Option.tagFileFormat > 1)

/*----------------------------------------------------------------------------
 *  Portability defines
 *--------------------------------------------------------------------------*/
#if !defined(HAVE_TRUNCATE) && !defined(HAVE_FTRUNCATE) && !defined(HAVE_CHSIZE)
# define USE_REPLACEMENT_TRUNCATE
#endif

/*  Hack for rediculous practice of Microsoft Visual C++.
 */
#if defined(WIN32) && defined(_MSC_VER)
# define chsize         _chsize
# define open           _open
# define close          _close
# define O_RDWR         _O_RDWR
#endif

/*============================================================================
=   Data definitions
============================================================================*/

tagFile TagFile = {
    NULL,               /* file name */
    NULL,               /* file pointer */
    { 0, 0 },           /* numTags */
    { 0, 0, 0 },        /* max */
    { "", NULL },       /* etags */
    NULL                /* vLine */
};

/*============================================================================
=   Function prototypes
============================================================================*/
#ifdef NEED_PROTO_TRUNCATE
extern int truncate __ARGS((const char *path, off_t length));
#endif

#ifdef NEED_PROTO_FTRUNCATE
extern int ftruncate __ARGS((int fd, off_t length));
#endif

static void writePseudoTag __ARGS((const char *const tagName, const char *const fileName, const char *const pattern));
static void updateSortedFlag __ARGS((const char *const line, FILE *const fp, const fpos_t *const pStartOfLine));
static void addPseudoTags __ARGS((void));
static long unsigned int updatePseudoTags __ARGS((FILE *const fp));
static boolean isValidTagAddress __ARGS((const char *const tag));
static boolean isCtagsLine __ARGS((const char *const tag));
static boolean isEtagsLine __ARGS((const char *const tag));
static boolean isTagFile __ARGS((const char *const filename));
static size_t writeSourceLine __ARGS((FILE *const fp, const char *const line));
static size_t writeCompactSourceLine __ARGS((FILE *const fp, const char *const line));
static void rememberMaxLengths __ARGS((const size_t nameLength, const size_t lineLength));
static int writeXrefEntry __ARGS((const tagEntryInfo *const tag));
static void truncateTagLine __ARGS((char *const line, const char *const token, const boolean discardNewline));
static int writeEtagsEntry __ARGS((const tagEntryInfo *const tag));
static int addExtensionFlags __ARGS((const tagEntryInfo *const tag));
static int writePatternEntry __ARGS((const tagEntryInfo *const tag));
static int writeLineNumberEntry __ARGS((const tagEntryInfo *const tag));
static int writeCtagsEntry __ARGS((const tagEntryInfo *const tag));

/*============================================================================
=   Function definitions
============================================================================*/

extern const char *const tagFileName()
{
    return TagFile.name;
}

/*----------------------------------------------------------------------------
*-      Pseudo tag support
----------------------------------------------------------------------------*/

static void writePseudoTag( tagName, fileName, pattern )
    const char *const tagName;
    const char *const fileName;
    const char *const pattern;
{
    const int length = fprintf(TagFile.fp, "%s%s\t%s\t/%s/\n",
                               PSEUDO_TAG_PREFIX, tagName, fileName, pattern);
    ++TagFile.numTags.added;
    rememberMaxLengths(strlen(tagName), (size_t)length);
}

static void addPseudoTags()
{
    if (! Option.xref)
    {
        char format[11];
        const char *formatComment = "unknown format";

        sprintf(format, "%u", Option.tagFileFormat);

        if (Option.tagFileFormat == 1)
            formatComment = "original ctags format";
        else if (Option.tagFileFormat == 2)
            formatComment =
                    "extended format; --format=1 will not append ;\" to lines";

        writePseudoTag("TAG_FILE_FORMAT", format, formatComment);
        writePseudoTag("TAG_FILE_SORTED", Option.sorted ? "1":"0",
                       "0=unsorted, 1=sorted");
        writePseudoTag("TAG_PROGRAM_AUTHOR",    AUTHOR_NAME,  AUTHOR_EMAIL);
        writePseudoTag("TAG_PROGRAM_NAME",      PROGRAM_NAME, "");
        writePseudoTag("TAG_PROGRAM_URL",       PROGRAM_URL,  "official site");
        writePseudoTag("TAG_PROGRAM_VERSION",   PROGRAM_VERSION,
                       "with C, C++, Eiffel, Fortran, and Java  support");
    }
}

static void updateSortedFlag( line, fp, pStartOfLine )
    const char *const line;
    FILE *const fp;
    const fpos_t *const pStartOfLine;
{
    const char *const tab = strchr(line, '\t');

    if (tab != NULL)
    {
        const long boolOffset = tab - line + 1;         /* where it should be */

        if (line[boolOffset] == '0'  ||  line[boolOffset] == '1')
        {
            fpos_t nextLine;

            if (fgetpos(fp, &nextLine) == -1 || fsetpos(fp, pStartOfLine) == -1)
                error(WARNING, "Failed to update 'sorted' pseudo-tag");
            else
            {
                fpos_t flagLocation;
                int c, d;

                do
                    c = fgetc(fp);
                while (c != '\t'  &&  c != '\n');
                fgetpos(fp, &flagLocation);
                d = fgetc(fp);
                if (c == '\t'  &&  (d == '0'  ||  d == '1')  &&
                    d != (int)Option.sorted)
                {
                    fsetpos(fp, &flagLocation);
                    fputc(Option.sorted ? '1' : '0', fp);
                }
                fsetpos(fp, &nextLine);
            }
        }
    }
}

/*  Look through all line beginning with "!_TAG_FILE", and update those which
 *  require it.
 */
static unsigned long updatePseudoTags( fp )
    FILE *const fp;
{
    enum { maxClassLength = 20 };
    char class[maxClassLength + 1];
    unsigned long linesRead = 0;
    fpos_t startOfLine;
    size_t classLength;
    const char *line;

    sprintf(class, "%sTAG_FILE", PSEUDO_TAG_PREFIX);
    classLength = strlen(class);
    Assert(classLength < maxClassLength);

    fgetpos(fp, &startOfLine);
    line = readLine(TagFile.vLine, fp);
    while (line != NULL  &&  line[0] == class[0])
    {
        ++linesRead;
        if (strncmp(line, class, classLength) == 0)
        {
            char tab, classType[16];

            if (sscanf(line + classLength, "%15s%c", classType, &tab) == 2  &&
                tab == '\t')
            {
                if (strcmp(classType, "_SORTED") == 0)
                    updateSortedFlag(line, fp, &startOfLine);
            }
            fgetpos(fp, &startOfLine);
        }
        line = readLine(TagFile.vLine, fp);
    }
    while (line != NULL)                        /* skip to end of file */
    {
        ++linesRead;
        line = readLine(TagFile.vLine, fp);
    }
    return linesRead;
}

/*----------------------------------------------------------------------------
 *  Tag file management
 *--------------------------------------------------------------------------*/

static boolean isValidTagAddress( excmd )
    const char *const excmd;
{
    boolean isValid = FALSE;

    if (strchr("/?", excmd[0]) != NULL)
        isValid = TRUE;
    else
    {
        char *address = (char *)eMalloc(strlen(excmd) + 1);

        if (address != NULL)
        {
            if (sscanf(excmd, "%[^;\n]", address) == 1  &&
                strspn(address,"0123456789") == strlen(address))
                    isValid = TRUE;
            free(address);
        }
    }
    return isValid;
}

static boolean isCtagsLine( line )
    const char *const line;
{
    enum fieldList { TAG, TAB1, SRC_FILE, TAB2, EXCMD, NUM_FIELDS };
    boolean ok = FALSE;                 /* we assume not unless confirmed */
    const size_t fieldLength = strlen(line) + 1;
    char *const fields = (char *)eMalloc((size_t)NUM_FIELDS * fieldLength);

    if (fields == NULL)
        error(FATAL, "Cannot analyze tag file");
    else
    {
#define field(x)        (fields + ((size_t)(x) * fieldLength))

        const int numFields = sscanf(line, "%[^\t]%[\t]%[^\t]%[\t]%[^\r\n]",
                                     field(TAG), field(TAB1), field(SRC_FILE),
                                     field(TAB2), field(EXCMD));

        /*  There must be exactly five fields: two tab fields containing
         *  exactly one tab each, the tag must not begin with "#", and the
         *  file name should not end with ";", and the excmd must be
         *  accceptable.
         *
         *  These conditions will reject tag-looking lines like:
         *      int     a;      <C-comment>
         *      #define LABEL   <C-comment>
         */
        if (numFields == NUM_FIELDS   &&
            strlen(field(TAB1)) == 1  &&
            strlen(field(TAB2)) == 1  &&
            field(TAG)[0] != '#'      &&
            field(SRC_FILE)[strlen(field(SRC_FILE)) - 1] != ';'  &&
            isValidTagAddress(field(EXCMD)))
                ok = TRUE;

        free(fields);
    }
    return ok;
}

static boolean isEtagsLine( line )
    const char *const line;
{
    const char *const magic = "\f\n";

    return (boolean)(strncmp(line, magic, strlen(magic)) == 0);
}

static boolean isTagFile( filename )
    const char *const filename;
{
    boolean ok = FALSE;                 /* we assume not unless confirmed */
    FILE *const fp = fopen(filename, "rb");

    if (fp == NULL  &&  errno == ENOENT)
        ok = TRUE;
    else if (fp != NULL)
    {
        const char *line = readLine(TagFile.vLine, fp);

        if (line == NULL)
            ok = TRUE;
        else if (Option.etags)          /* check for etags magic number */
            ok = isEtagsLine(line);
        else
            ok = isCtagsLine(line);
        fclose(fp);
    }
    return ok;
}

extern void openTagFile( toStdout )
    const boolean toStdout;
{
    static char tempName[L_tmpnam];

    if (TagFile.vLine == NULL)
        TagFile.vLine = vStringNew();

    /*  Open the tags file.
     */
    if (toStdout)
    {
        TagFile.name = tmpnam(tempName);
        TagFile.fp = fopen(TagFile.name, "w");
    }
    else
    {
        const char *const fname  = Option.tagFileName;
        const boolean fileExists = doesFileExist(fname);

        TagFile.name = fname;
        if (fileExists  &&  ! isTagFile(fname))
            error(FATAL,
              "\"%s\" doesn't look like a tag file; I refuse to overwrite it.",
                  fname);

        if (Option.etags)
        {
            if (Option.append  &&  fileExists)
                TagFile.fp = fopen(fname, "a+b");
            else
                TagFile.fp = fopen(fname, "w+b");
        }
        else
        {
            if (Option.append  &&  fileExists)
            {
                TagFile.fp = fopen(fname, "r+");
                if (TagFile.fp != NULL)
                {
                    TagFile.numTags.prev = updatePseudoTags(TagFile.fp);
                    fclose(TagFile.fp);
                    TagFile.fp = fopen(fname, "a+");
                }
            }
            else
            {
                TagFile.fp = fopen(fname, "w");
                if (TagFile.fp != NULL)
                    addPseudoTags();
            }
        }
        if (TagFile.fp == NULL)
        {
            error(FATAL | PERROR, "cannot open tag file");
            exit(1);
        }
    }
}

#ifdef USE_REPLACEMENT_TRUNCATE

static int copyChars __ARGS((FILE *const fpFrom, FILE *const fpTo, const long size));
static int copyFile __ARGS((const char *const from, const char *const to, const long size));
static int replacementTruncate __ARGS((const char *const name, const long size));

static int copyChars( fpFrom, fpTo, size )
    FILE *const fpFrom;
    FILE *const fpTo;
    const long size;
{
    int result = -1;
    long count;

    for (count = 0  ;  count < size  ;  ++count)
    {
        const int c = getc(fpFrom);

        if (c == EOF  ||  putc(c, fpTo) == EOF)
            break;
    }
    if (count == size)
        result = 0;
    return result;
}

static int copyFile( from, to, size )
    const char *const from;
    const char *const to;
    const long size;
{
    int result = -1;
    FILE *const fpFrom = fopen(from, "rb");

    if (fpFrom != NULL)
    {
        FILE *const fpTo = fopen(to, "wb");

        if (fpFrom != NULL)
        {
            result = copyChars(fpFrom, fpTo, size);
            if (result == 0)
                result = fclose(fpTo);
        }
        if (result == 0)
            result = fclose(fpFrom);
    }
    return result;
}

/*  Replacement for missing library function.
 */
static int replacementTruncate( name, size )
    const char *const name;
    const long size;
{
    char tempName[L_tmpnam];
    int result = -1;

    if (tmpnam(tempName) != NULL)
    {
        result = copyFile(name, tempName, size);
        if (result == 0)
            result = copyFile(tempName, name, size);
        if (result == 0)
            result = remove(tempName);
    }
    return result;
}

#endif

extern void closeTagFile( resize )
    const boolean resize;
{
    const long __unused__ size = ftell(TagFile.fp);

    fclose(TagFile.fp);
    if (resize)
    {
        int __unused__ result = 0;

#ifdef USE_REPLACEMENT_TRUNCATE
        result = replacementTruncate(TagFile.name, size);
#else
# ifdef HAVE_TRUNCATE
        result = truncate(TagFile.name, (off_t)size);
# else
        const int fd = open(TagFile.name, O_RDWR);

        if (fd != -1)
        {
#  ifdef HAVE_FTRUNCATE
            result = ftruncate(fd, (off_t)size);
#  else
#   ifdef HAVE_CHSIZE
            result = chsize(fd, size);
#   endif
#  endif
            close(fd);
        }
# endif
#endif
        if (result == -1)
            fprintf(errout, "Cannot shorten tag file: errno = %d\n", errno);
    }
}

extern void beginEtagsFile()
{
    tmpnam(TagFile.etags.name);
    TagFile.etags.fp = fopen(TagFile.etags.name, "w+b");
    if (TagFile.etags.fp == NULL)
        error(FATAL | PERROR, "cannot open \"%s\"", TagFile.etags.name);
    TagFile.etags.byteCount = 0;
}

extern void endEtagsFile( name )
    const char *const name;
{
    const char *line;

    fprintf(TagFile.fp, "\f\n%s,%ld\n", name, (long)TagFile.etags.byteCount);
    if (TagFile.etags.fp != NULL)
    {
        rewind(TagFile.etags.fp);
        while ((line = readLine(TagFile.vLine, TagFile.etags.fp)) != NULL)
            fputs(line, TagFile.fp);
        fclose(TagFile.etags.fp);
        remove(TagFile.etags.name);
    }
    TagFile.etags.name[0] = '\0';
}

/*----------------------------------------------------------------------------
 *  Tag entry management
 *--------------------------------------------------------------------------*/

/*  This function copies the current line out to a specified file. It has no
 *  effect on the fileGetc() function.  During copying, any '\' characters
 *  are doubled and a leading '^' or trailing '$' is also quoted. End of line
 *  characters (line feed or carriage return) are dropped.
 */
static size_t writeSourceLine( fp, line )
    FILE *const fp;
    const char *const line;
{
    size_t length = 0;
    const char *p;

    /*  Write everything up to, but not including, a line end character.
     */
    for (p = line  ;  *p != '\0'  ;  ++p)
    {
        const int next = *(p + 1);
        const int c = *p;

        if (c == CRETURN  ||  c == NEWLINE)
            break;

        /*  If character is '\', or a terminal '$', then quote it.
         */
        if (c == BACKSLASH  ||  c == (Option.backward ? '?' : '/')  ||
            (c == '$'  &&  (next == NEWLINE  ||  next == CRETURN)))
        {
            putc(BACKSLASH, fp);
            ++length;
        }
        putc(c, fp);
        ++length;
    }
    return length;
}

/*  Writes "line", stripping leading and duplicate white space.
 */
static size_t writeCompactSourceLine( fp, line )
    FILE *const fp;
    const char *const line;
{
    boolean lineStarted = FALSE;
    size_t  length = 0;
    const char *p;
    int c;

    /*  Write everything up to, but not including, the newline.
     */
    for (p = line, c = *p  ;  c != NEWLINE  &&  c != '\0'  ;  c = *++p)
    {
        if (lineStarted  || ! isspace(c))       /* ignore leading spaces */
        {
            lineStarted = TRUE;
            if (isspace(c))
            {
                int next;

                /*  Consume repeating white space.
                 */
                while (next = *(p+1) , isspace(next)  &&  next != NEWLINE)
                    ++p;
                c = ' ';        /* force space character for any white space */
            }
            if (c != CRETURN  ||  *(p + 1) != NEWLINE)
            {
                putc(c, fp);
                ++length;
            }
        }
    }
    return length;
}

static void rememberMaxLengths( nameLength, lineLength )
    const size_t nameLength;
    const size_t lineLength;
{
    if (nameLength > TagFile.max.tag)
        TagFile.max.tag = nameLength;

    if (lineLength > TagFile.max.line)
        TagFile.max.line = lineLength;
}

static int writeXrefEntry( tag )
    const tagEntryInfo *const tag;
{
    const char *const line = readSourceLine(TagFile.vLine, &tag->filePosition,
                                            NULL);
    int length = fprintf(TagFile.fp, "%-20s %-10s %4lu  %-14s ", tag->name,
                         tag->kindName, tag->lineNumber, tag->sourceFileName);

    length += writeCompactSourceLine(TagFile.fp, line);
    putc(NEWLINE, TagFile.fp);
    ++length;

    return length;
}

/*  Truncates the text line containing the tag at the character following the
 *  tag, providing a character which designates the end of the tag.
 */
static void truncateTagLine( line, token, discardNewline )
    char *const line;
    const char *const token;
    const boolean discardNewline;
{
    char *p = strstr(line, token);

    if (p != NULL)
    {
        p += strlen(token);
        if (*p != '\0'  &&  !(*p == '\n'  &&  discardNewline))
            ++p;                /* skip past character terminating character */
        *p = '\0';
    }
}

static int writeEtagsEntry( tag )
    const tagEntryInfo *const tag;
{
    int length;

    if (tag->isFileEntry)
        length = fprintf(TagFile.etags.fp, "\177%s\001%lu,0\n",
                         tag->name, tag->lineNumber);
    else
    {
        long seekValue;
        char *const line = readSourceLine(TagFile.vLine, &tag->filePosition,
                                          &seekValue);

        truncateTagLine(line, tag->name, TRUE);

        if (tag->etagsIncName)
            length = fprintf(TagFile.etags.fp, "%s\177%s\001%lu,%ld\n", line,
                             tag->name, tag->lineNumber, seekValue);
        else
            length = fprintf(TagFile.etags.fp, "%s\177%lu,%ld\n", line,
                             tag->lineNumber, seekValue);
    }
    TagFile.etags.byteCount += length;

    return length;
}

static int addExtensionFlags( tag )
    const tagEntryInfo *const tag;
{
    const char *const prefix = ";\"\t";
    const char *const separator = "\t";
    unsigned int i;
    int length = 0;

    /*  Add an extension flag designating that the type of the tag.
     */
    if (Option.kindLong)
        length += fprintf(TagFile.fp, "%s%s", prefix, tag->kindName);
    else
        length += fprintf(TagFile.fp, "%s%c", prefix, tag->kind);

    /*  If this is a static tag, add the appropriate extension flag.
     */
    if (tag->isFileScope)
        length += fprintf(TagFile.fp, "%sfile:", separator);

    /*  Add any other extension flags.
     */
    for (i = 0  ;  i < tag->otherFields.count  ;  ++i)
    {
        const char *const label = tag->otherFields.label[i];
        const char *const value = tag->otherFields.value[i];

        if (label != NULL)
            length += fprintf(TagFile.fp, "%s%s: %s", separator,
                              label, value == NULL ? "" : value);
    }

    return length;
}

static int writePatternEntry( tag )
    const tagEntryInfo *const tag;
{
    char *const line = readSourceLine(TagFile.vLine, &tag->filePosition, NULL);
    const int searchChar = Option.backward ? '?' : '/';
    boolean newlineTerminated;
    int length = 0;

    if (tag->ctagsTruncate)
        truncateTagLine(line, tag->name, FALSE);
    newlineTerminated = (boolean)(strchr("\n\r", line[strlen(line)-1]) != NULL);

    length += fprintf(TagFile.fp, "%c^", searchChar);
    length += writeSourceLine(TagFile.fp, line);
    length += fprintf(TagFile.fp, "%s%c", newlineTerminated ? "$":"",
                      searchChar);

    return length;
}

static int writeLineNumberEntry( tag )
    const tagEntryInfo *const tag;
{
    return fprintf(TagFile.fp, "%lu", tag->lineNumber);
}

static int writeCtagsEntry( tag )
    const tagEntryInfo *const tag;
{
    int length = fprintf(TagFile.fp, "%s\t%s\t", tag->name,tag->sourceFileName);

    if (tag->lineNumberEntry)
        length += writeLineNumberEntry(tag);
    else
        length += writePatternEntry(tag);

    if (includeExtensionFlags())
        length += addExtensionFlags(tag);

    length += fprintf(TagFile.fp, "\n");

    return length;
}

extern void makeTagEntry( tag )
    const tagEntryInfo *const tag;
{
    int length = 0;

    DebugStatement( debugEntry(tag); )

    if (Option.xref)
    {
        if (! tag->isFileEntry)
            length = writeXrefEntry(tag);
    }
    else if (Option.etags)
        length = writeEtagsEntry(tag);
    else
        length = writeCtagsEntry(tag);

    ++TagFile.numTags.added;
    rememberMaxLengths(strlen(tag->name), (size_t)length);
}

extern void initTagEntry( e, name )
    tagEntryInfo *const e;
    const char *const name;
{
    e->lineNumberEntry  = (boolean)(Option.locate == EX_LINENUM);
    e->lineNumber       = getFileLine();
    e->filePosition     = getFilePosition();
    e->isFileScope      = FALSE;
    e->isFileEntry      = FALSE;
    e->ctagsTruncate    = FALSE;
    e->etagsIncName     = FALSE;
    e->sourceFileName   = getFileName();
    e->name             = name;
    e->kindName         = "";
    e->kind             = ' ';
    e->otherFields.count = 0;
    e->otherFields.label = NULL;
    e->otherFields.value = NULL;
}

/* vi:set tabstop=8 shiftwidth=4: */
Last modification: Thursday December 5, 2002 at 15:16:30 (EST)