view lib-src/mmencode.c @ 2362:6aa56b089139

[xemacs-hg @ 2004-11-02 09:51:04 by ben] To: xemacs-patches@xemacs.org internals/index.texi: Deleted. Incorporated into internals.texi. Having a separate index file messes up texinfo-master-menu. internals/internals.texi: Add bunches and bunches and bunches and bunches of stuff, taken from documentation floating around in various places -- text.c, file-coding.c, other .c and .h files, stuff that I wrote up for an old XEmacs contract, proposals written up in the process of an e-mail discussion, etc. Fix up some mistakes, esp. in CCL. Extra crap from CCL, duplicated with Lispref, removed. Sections on Old Future Work and Future Work Discussion added. Bunches of other work. Add bunches of documentation taken from the source code. Fixup various places to use @strong{}, @code{}, @file{}. Create new Text chapter, split off from Buffers and Textual Representation. Create new chapter for MS Windows, mostly written from scratch. Consolidate all Mule info under "Multilingual Support". Break up chapter on modules and move some parts to the sections discussing the modules, for consolidation purposes. Add a big cross-reference table for all the modules to where they're discussed (or not). New chapter Asynchronous Events; Quit Checking. (Taken from various parts of the code.) New Introduction. New section on Focus Handling (from the code). NOTE that in the process, I discovered that we essentially have FOUR redundant introductions to Mule issues! Someone really needs to go through and clean them up and integrate them (sjt?).
author ben
date Tue, 02 Nov 2004 09:51:18 +0000
parents b39c14581166
children 49316578f12d
line wrap: on
line source

/*
Copyright (c) 1991 Bell Communications Research, Inc. (Bellcore)

Permission to use, copy, modify, and distribute this material 
for any purpose and without fee is hereby granted, provided 
that the above copyright notice and this permission notice 
appear in all copies, and that the name of Bellcore not be 
used in advertising or publicity pertaining to this 
material without the specific, prior written permission 
of an authorized representative of Bellcore.  BELLCORE 
MAKES NO REPRESENTATIONS ABOUT THE ACCURACY OR SUITABILITY 
OF THIS MATERIAL FOR ANY PURPOSE.  IT IS PROVIDED "AS IS", 
WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES.
*/

#define NEWLINE_CHAR '\n'
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <errno.h>

static void
output64chunk(int c1, int c2, int c3, int pads, FILE *outfile);

static signed char basis_64[] =
   "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

static signed char index_64[128] = {
    -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
    -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
    -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,62, -1,-1,-1,63,
    52,53,54,55, 56,57,58,59, 60,61,-1,-1, -1,-1,-1,-1,
    -1, 0, 1, 2,  3, 4, 5, 6,  7, 8, 9,10, 11,12,13,14,
    15,16,17,18, 19,20,21,22, 23,24,25,-1, -1,-1,-1,-1,
    -1,26,27,28, 29,30,31,32, 33,34,35,36, 37,38,39,40,
    41,42,43,44, 45,46,47,48, 49,50,51,-1, -1,-1,-1,-1
};

#define char64(c)  (((c) < 0 || (c) > 127) ? -1 : index_64[(c)])

/*
char64(c)
char c;
{
    char *s = (char *) strchr(basis_64, c);
    if (s) return(s-basis_64);
    return(-1);
}
*/

/* the following gets a character, but fakes it properly into two chars if there's a newline character */
static int InNewline=0;

static int
nextcharin (FILE *infile, int PortableNewlines)
{
    int c;

#ifndef NEWLINE_CHAR
    return(getc(infile));
#else
    if (!PortableNewlines) return(getc(infile));
    if (InNewline) {
        InNewline = 0;
        return(10); /* LF */
    }
    c = getc(infile);
    if (c == NEWLINE_CHAR) {
        InNewline = 1;
        return(13); /* CR */
    }
    return(c);
#endif
}

static void
to64(FILE *infile, FILE *outfile, int PortableNewlines) 
{
    int c1, c2, c3, ct=0;
    InNewline = 0; /* always reset it */
    while ((c1 = nextcharin(infile, PortableNewlines)) != EOF) {
        c2 = nextcharin(infile, PortableNewlines);
        if (c2 == EOF) {
            output64chunk(c1, 0, 0, 2, outfile);
        } else {
            c3 = nextcharin(infile, PortableNewlines);
            if (c3 == EOF) {
                output64chunk(c1, c2, 0, 1, outfile);
            } else {
                output64chunk(c1, c2, c3, 0, outfile);
            }
        }
        ct += 4;
        if (ct > 71) {
            putc('\n', outfile);
            ct = 0;
        }
    }
    if (ct) putc('\n', outfile);
    fflush(outfile);
}

static void
output64chunk(int c1, int c2, int c3, int pads, FILE *outfile)
{
    putc(basis_64[c1>>2], outfile);
    putc(basis_64[((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4)], outfile);
    if (pads == 2) {
        putc('=', outfile);
        putc('=', outfile);
    } else if (pads) {
        putc(basis_64[((c2 & 0xF) << 2) | ((c3 & 0xC0) >>6)], outfile);
        putc('=', outfile);
    } else {
        putc(basis_64[((c2 & 0xF) << 2) | ((c3 & 0xC0) >>6)], outfile);
        putc(basis_64[c3 & 0x3F], outfile);
    }
}

static int
PendingBoundary(char *s, char **Boundaries, int *BoundaryCt)
{
    int i, len;

    if (s[0] != '-' || s[1] != '-') return(0);


    for (i=0; i < *BoundaryCt; ++i) {
	len = strlen(Boundaries[i]);
        if (!strncmp(s, Boundaries[i], len)) {
            if (s[len] == '-' && s[len+1] == '-') *BoundaryCt = i;
            return(1);
        }
    }
    return(0);
}

/* If we're in portable newline mode, we have to convert CRLF to the 
    local newline convention on output */

static int CRpending = 0;

#ifdef NEWLINE_CHAR
static void
almostputc(int c, FILE *outfile, int PortableNewlines)
{
    if (CRpending) {
        if (c == 10) {
            putc(NEWLINE_CHAR, outfile);
            CRpending = 0;
        } else {
            putc(13, outfile);
	    if (c != 13) {
            	putc(c, outfile);
		CRpending = 0;
	    }
        }
    } else {
        if (PortableNewlines && c == 13) {
            CRpending = 1;
        } else {
            putc(c, outfile);
        }
    }
}
#else
static void
almostputc(int c, FILE *outfile, int PortableNewlines)
{
    putc(c, outfile);
}
#endif

static void
from64(FILE *infile, FILE *outfile,
       char **boundaries, int *boundaryct, int PortableNewlines) 
{
    int c1, c2, c3, c4;
    int newline = 1, DataDone = 0;

    /* always reinitialize */
    CRpending = 0;
    while ((c1 = getc(infile)) != EOF) {
        if (isspace(c1)) {
            if (c1 == '\n') {
                newline = 1;
            } else {
                newline = 0;
            }
            continue;
        }
        if (newline && boundaries && c1 == '-') {
            char Buf[200];
            /* a dash is NOT base 64, so all bets are off if NOT a boundary */
            ungetc(c1, infile);
            fgets(Buf, sizeof(Buf), infile);
            if (boundaries
                 && (Buf[0] == '-')
                 && (Buf[1] == '-')
                 && PendingBoundary(Buf, boundaries, boundaryct)) {
                return;
            }
            fprintf(stderr, "Ignoring unrecognized boundary line: %s\n", Buf);
            continue;
        }
        if (DataDone) continue;
        newline = 0;
        do {
            c2 = getc(infile);
        } while (c2 != EOF && isspace(c2));
        do {
            c3 = getc(infile);
        } while (c3 != EOF && isspace(c3));
        do {
            c4 = getc(infile);
        } while (c4 != EOF && isspace(c4));
        if (c2 == EOF || c3 == EOF || c4 == EOF) {
            fprintf(stderr, "Warning: base64 decoder saw premature EOF!\n");
            return;
        }
        if (c1 == '=' || c2 == '=') {
            DataDone=1;
            continue;
        }
        c1 = char64(c1);
        c2 = char64(c2);
        almostputc(((c1<<2) | ((c2&0x30)>>4)), outfile, PortableNewlines);
        if (c3 == '=') {
            DataDone = 1;
        } else {
            c3 = char64(c3);
            almostputc((((c2&0XF) << 4) | ((c3&0x3C) >> 2)), outfile, PortableNewlines);
            if (c4 == '=') {
                DataDone = 1;
            } else {
                c4 = char64(c4);
                almostputc((((c3&0x03) <<6) | c4), outfile, PortableNewlines);
            }
        }
    }
    if (CRpending) putc(13, outfile); /* Don't drop a lone trailing char 13 */
}

static signed char basis_hex[] = "0123456789ABCDEF";
static signed char index_hex[128] = {
    -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
    -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
    -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
     0, 1, 2, 3,  4, 5, 6, 7,  8, 9,-1,-1, -1,-1,-1,-1,
    -1,10,11,12, 13,14,15,-1, -1,-1,-1,-1, -1,-1,-1,-1,
    -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
    -1,10,11,12, 13,14,15,-1, -1,-1,-1,-1, -1,-1,-1,-1,
    -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1
};

/* The following version generated complaints on Solaris. */
/* #define hexchar(c)  (((c) < 0 || (c) > 127) ? -1 : index_hex[(c)])  */
/*  Since we're no longer ever calling it with anything signed, this should work: */
#define hexchar(c)  (((c) > 127) ? -1 : index_hex[(c)])

/*
hexchar(c)
char c;
{
    char *s;
    if (islower(c)) c = toupper(c);
    s = (char *) strchr(basis_hex, c);
    if (s) return(s-basis_hex);
    return(-1);
}
*/

static void
toqp(FILE *infile, FILE *outfile) 
{
    int c, ct=0, prevc=255;
    while ((c = getc(infile)) != EOF) {
        if ((c < 32 && (c != '\n' && c != '\t'))
             || (c == '=')
             || (c >= 127)
             /* Following line is to avoid single periods alone on lines,
               which messes up some dumb smtp implementations, sigh... */
             || (ct == 0 && c == '.')) {
            putc('=', outfile);
            putc(basis_hex[c>>4], outfile);
            putc(basis_hex[c&0xF], outfile);
            ct += 3;
            prevc = 'A'; /* close enough */
        } else if (c == '\n') {
            if (prevc == ' ' || prevc == '\t') {
                putc('=', outfile); /* soft & hard lines */
                putc(c, outfile);
            }
            putc(c, outfile);
            ct = 0;
            prevc = c;
        } else {
            if (c == 'F' && prevc == '\n') {
                /* HORRIBLE but clever hack suggested by MTR for sendmail-avoidance */
                c = getc(infile);
                if (c == 'r') {
                    c = getc(infile);
                    if (c == 'o') {
                        c = getc(infile);
                        if (c == 'm') {
                            c = getc(infile);
                            if (c == ' ') {
                                /* This is the case we are looking for */
                                fputs("=46rom", outfile);
                                ct += 6;
                            } else {
                                fputs("From", outfile);
                                ct += 4;
                            }
                        } else {
                            fputs("Fro", outfile);
                            ct += 3;
                        }
                    } else {
                        fputs("Fr", outfile);
                        ct += 2;
                    }
                } else {
                    putc('F', outfile);
                    ++ct;
                }
                ungetc(c, infile);
                prevc = 'x'; /* close enough -- printable */
            } else { /* END horrible hack */
                putc(c, outfile);
                ++ct;
                prevc = c;
            }
        }
        if (ct > 72) {
            putc('=', outfile);
            putc('\n', outfile);
            ct = 0;
            prevc = '\n';
        }
    }
    if (ct) {
        putc('=', outfile);
        putc('\n', outfile);
    }
}

static void
fromqp(FILE *infile, FILE *outfile, char **boundaries, int *boundaryct) 
{
    int c1, c2;
    int sawnewline = 1, neednewline = 0;
    /* The neednewline hack is necessary because the newline leading into 
      a multipart boundary is part of the boundary, not the data */

    while ((c1 = getc(infile)) != EOF) {
        if (sawnewline && boundaries && (c1 == '-')) {
            char Buf[200];
            unsigned char *s;

            ungetc(c1, infile);
            fgets(Buf, sizeof(Buf), infile);
            if (boundaries
                 && (Buf[0] == '-')
                 && (Buf[1] == '-')
                 && PendingBoundary(Buf, boundaries, boundaryct)) {
                return;
            }
            /* Not a boundary, now we must treat THIS line as q-p, sigh */
            if (neednewline) {
                putc('\n', outfile);
                neednewline = 0;
            }
            for (s=(unsigned char *) Buf; *s; ++s) {
                if (*s == '=') {
                    if (!*++s) break;
                    if (*s == '\n') {
                        /* ignore it */
                        sawnewline = 1;
                    } else {
                        c1 = hexchar(*s);
                        if (!*++s) break;
                        c2 = hexchar(*s);
                        putc(c1<<4 | c2, outfile);
                    }
                } else {
#ifdef WIN32_NATIVE
                    if (*s == '\n')
                        putc('\r', outfile);	/* insert CR for binary-mode write */
#endif
                    putc(*s, outfile);
                }
            }
        } else {
            if (neednewline) {
                putc('\n', outfile);
                neednewline = 0;
            }
            if (c1 == '=') {
                sawnewline = 0;
                c1 = getc(infile);
                if (c1 == '\n') {
                    /* ignore it */
                    sawnewline = 1;
                } else {
                    c2 = getc(infile);
                    c1 = hexchar(c1);
                    c2 = hexchar(c2);
                    putc(c1<<4 | c2, outfile);
                    if (c2 == '\n') sawnewline = 1;
                }
            } else {
                if (c1 == '\n') {
                    sawnewline = 1;
                    neednewline = 1;
                } else {
                    sawnewline = 0;
                    putc(c1, outfile);
                }
            }
        }
    }
    if (neednewline) {
        putc('\n', outfile);
        neednewline = 0;
    }    
}


/*
Copyright (c) 1991 Bell Communications Research, Inc. (Bellcore)

Permission to use, copy, modify, and distribute this material 
for any purpose and without fee is hereby granted, provided 
that the above copyright notice and this permission notice 
appear in all copies, and that the name of Bellcore not be 
used in advertising or publicity pertaining to this 
material without the specific, prior written permission 
of an authorized representative of Bellcore.  BELLCORE 
MAKES NO REPRESENTATIONS ABOUT THE ACCURACY OR SUITABILITY 
OF THIS MATERIAL FOR ANY PURPOSE.  IT IS PROVIDED "AS IS", 
WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES.
*/
#ifdef WIN32_NATIVE
#include <io.h>
#include <fcntl.h>
#endif

#define BASE64 1
#define QP 2 /* quoted-printable */

int main(int argc, char *argv[])
{
    int encode = 1, which = BASE64, i, portablenewlines = 0;
    FILE *fp = stdin;
    FILE *fpo = stdout;

    for (i=1; i<argc; ++i) {
        if (argv[i][0] == '-') {
	    switch (argv[i][1]) {
		case 'o':
		    if (++i >= argc) {
			fprintf(stderr, "mimencode: -o requires a file name.\n");
			exit(-1);
		    }
		    fpo = fopen(argv[i], "w");
		    if (!fpo) {
			perror(argv[i]);
			exit(-1);
		    }
		    break;
                case 'u':
                    encode = 0;
                    break;
                case 'q':
                    which = QP;
                    break;
                case 'p':
                    portablenewlines = 1;
                    break;
                case 'b':
                    which = BASE64;
                    break;
		default:
                    fprintf(stderr,
                       "Usage: mmencode [-u] [-q] [-b] [-p] [-o outputfile] [file name]\n");
                    exit(-1);
            }
        } else {
#ifdef WIN32_NATIVE
            if (encode)
                fp = fopen(argv[i], "rb");
            else
            {
                fp = fopen(argv[i], "rt");
                setmode(fileno(fpo), O_BINARY);
            } /* else */
#else
            fp = fopen(argv[i], "r");
#endif /* WIN32_NATIVE */
            if (!fp) {
                perror(argv[i]);
                exit(-1);
            }
        }
    }
#ifdef WIN32_NATIVE
    if (fp == stdin) setmode(fileno(fp), O_BINARY);
#endif /* WIN32_NATIVE */
    if (which == BASE64) {
        if (encode) {
            to64(fp, fpo, portablenewlines);
        } else {
            from64(fp,fpo, (char **) NULL, (int *) 0, portablenewlines);
        }
    } else {
        if (encode) toqp(fp, fpo); else fromqp(fp, fpo, NULL, 0);
    }
    return(0);
}