/
mime.c
1634 lines (1553 loc) · 35 KB
/
mime.c
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/*
* Heirloom mailx - a mail user agent derived from Berkeley Mail.
*
* Copyright (c) 2000-2004 Gunnar Ritter, Freiburg i. Br., Germany.
*/
/*
* Copyright (c) 2000
* Gunnar Ritter. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Gunnar Ritter
* and his contributors.
* 4. Neither the name of Gunnar Ritter nor the names of his contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY GUNNAR RITTER AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL GUNNAR RITTER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
#ifdef DOSCCS
static char copyright[]
= "@(#) Copyright (c) 2000, 2002 Gunnar Ritter. All rights reserved.\n";
static char sccsid[] = "@(#)mime.c 2.71 (gritter) 7/5/10";
#endif /* DOSCCS */
#endif /* not lint */
#include "rcv.h"
#include "extern.h"
#include <ctype.h>
#include <errno.h>
#ifdef HAVE_WCTYPE_H
#include <wctype.h>
#endif /* HAVE_WCTYPE_H */
/*
* Mail -- a mail program
*
* MIME support functions.
*/
/*
* You won't guess what these are for.
*/
static const char basetable[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
static char *mimetypes_world = "/etc/mime.types";
static char *mimetypes_user = "~/.mime.types";
char *us_ascii = "us-ascii";
static int mustquote_body(int c);
static int mustquote_hdr(const char *cp, int wordstart, int wordend);
static int mustquote_inhdrq(int c);
static size_t delctrl(char *cp, size_t sz);
static char *getcharset(int isclean);
static int has_highbit(register const char *s);
#ifdef HAVE_ICONV
static void uppercopy(char *dest, const char *src);
static void stripdash(char *p);
static size_t iconv_ft(iconv_t cd, char **inb, size_t *inbleft,
char **outb, size_t *outbleft);
static void invalid_seq(int c);
#endif /* HAVE_ICONV */
static int is_this_enc(const char *line, const char *encoding);
static char *mime_tline(char *x, char *l);
static char *mime_type(char *ext, char *filename);
static enum mimeclean mime_isclean(FILE *f);
static enum conversion gettextconversion(void);
static char *ctohex(int c, char *hex);
static size_t mime_write_toqp(struct str *in, FILE *fo, int (*mustquote)(int));
static void mime_str_toqp(struct str *in, struct str *out,
int (*mustquote)(int), int inhdr);
static void mime_fromqp(struct str *in, struct str *out, int ishdr);
static size_t mime_write_tohdr(struct str *in, FILE *fo);
static size_t convhdra(char *str, size_t len, FILE *fp);
static size_t mime_write_tohdr_a(struct str *in, FILE *f);
static void addstr(char **buf, size_t *sz, size_t *pos, char *str, size_t len);
static void addconv(char **buf, size_t *sz, size_t *pos, char *str, size_t len);
static size_t fwrite_td(void *ptr, size_t size, size_t nmemb, FILE *f,
enum tdflags flags, char *prefix, size_t prefixlen);
/*
* Check if c must be quoted inside a message's body.
*/
static int
mustquote_body(int c)
{
if (c != '\n' && (c < 040 || c == '=' || c >= 0177))
return 1;
return 0;
}
/*
* Check if c must be quoted inside a message's header.
*/
static int
mustquote_hdr(const char *cp, int wordstart, int wordend)
{
int c = *cp & 0377;
if (c != '\n' && (c < 040 || c >= 0177))
return 1;
if (wordstart && cp[0] == '=' && cp[1] == '?')
return 1;
if (cp[0] == '?' && cp[1] == '=' &&
(wordend || cp[2] == '\0' || whitechar(cp[2]&0377)))
return 1;
return 0;
}
/*
* Check if c must be quoted inside a quoting in a message's header.
*/
static int
mustquote_inhdrq(int c)
{
if (c != '\n'
&& (c <= 040 || c == '=' || c == '?' || c == '_' || c >= 0177))
return 1;
return 0;
}
static size_t
delctrl(char *cp, size_t sz)
{
size_t x = 0, y = 0;
while (x < sz) {
if (!cntrlchar(cp[x]&0377))
cp[y++] = cp[x];
x++;
}
return y;
}
/*
* Check if a name's address part contains invalid characters.
*/
int
mime_name_invalid(char *name, int putmsg)
{
char *addr, *p;
int in_quote = 0, in_domain = 0, err = 0, hadat = 0;
if (is_fileaddr(name))
return 0;
addr = skin(name);
if (addr == NULL || *addr == '\0')
return 1;
for (p = addr; *p != '\0'; p++) {
if (*p == '\"') {
in_quote = !in_quote;
} else if (*p < 040 || (*p & 0377) >= 0177) {
err = *p & 0377;
break;
} else if (in_domain == 2) {
if ((*p == ']' && p[1] != '\0') || *p == '\0'
|| *p == '\\' || whitechar(*p & 0377)) {
err = *p & 0377;
break;
}
} else if (in_quote && in_domain == 0) {
/*EMPTY*/;
} else if (*p == '\\' && p[1] != '\0') {
p++;
} else if (*p == '@') {
if (hadat++) {
if (putmsg) {
fprintf(stderr, catgets(catd, CATSET,
142,
"%s contains invalid @@ sequence\n"),
addr);
putmsg = 0;
}
err = *p;
break;
}
if (p[1] == '[')
in_domain = 2;
else
in_domain = 1;
continue;
} else if (*p == '(' || *p == ')' || *p == '<' || *p == '>'
|| *p == ',' || *p == ';' || *p == ':'
|| *p == '\\' || *p == '[' || *p == ']') {
err = *p & 0377;
break;
}
hadat = 0;
}
if (err && putmsg) {
fprintf(stderr, catgets(catd, CATSET, 143,
"%s contains invalid character '"), addr);
#ifdef HAVE_SETLOCALE
if (isprint(err))
#else /* !HAVE_SETLOCALE */
if (err >= 040 && err <= 0177)
#endif /* !HAVE_SETLOCALE */
putc(err, stderr);
else
fprintf(stderr, "\\%03o", err);
fprintf(stderr, catgets(catd, CATSET, 144, "'\n"));
}
return err;
}
/*
* Check all addresses in np and delete invalid ones.
*/
struct name *
checkaddrs(struct name *np)
{
struct name *n = np;
while (n != NULL) {
if (mime_name_invalid(n->n_name, 1)) {
if (n->n_blink)
n->n_blink->n_flink = n->n_flink;
if (n->n_flink)
n->n_flink->n_blink = n->n_blink;
if (n == np)
np = n->n_flink;
}
n = n->n_flink;
}
return np;
}
static char defcharset[] = "utf-8";
/*
* Get the character set dependant on the conversion.
*/
static char *
getcharset(int isclean)
{
char *charset;
if (isclean & (MIME_CTRLCHAR|MIME_HASNUL))
charset = NULL;
else if (isclean & MIME_HIGHBIT) {
charset = (wantcharset && wantcharset != (char *)-1) ?
wantcharset : value("charset");
if (charset == NULL) {
charset = defcharset;
}
} else {
/*
* This variable shall remain undocumented because
* only experts should change it.
*/
charset = value("charset7");
if (charset == NULL) {
charset = us_ascii;
}
}
return charset;
}
/*
* Get the setting of the terminal's character set.
*/
char *
gettcharset(void)
{
char *t;
if ((t = value("ttycharset")) == NULL)
if ((t = value("charset")) == NULL)
t = defcharset;
return t;
}
static int
has_highbit(const char *s)
{
if (s) {
do
if (*s & 0200)
return 1;
while (*s++ != '\0');
}
return 0;
}
static int
name_highbit(struct name *np)
{
while (np) {
if (has_highbit(np->n_name) || has_highbit(np->n_fullname))
return 1;
np = np->n_flink;
}
return 0;
}
char *
need_hdrconv(struct header *hp, enum gfield w)
{
if (w & GIDENT) {
if (hp->h_from && name_highbit(hp->h_from))
goto needs;
else if (has_highbit(myaddrs(hp)))
goto needs;
if (hp->h_organization && has_highbit(hp->h_organization))
goto needs;
else if (has_highbit(value("ORGANIZATION")))
goto needs;
if (hp->h_replyto && name_highbit(hp->h_replyto))
goto needs;
else if (has_highbit(value("replyto")))
goto needs;
if (hp->h_sender && name_highbit(hp->h_sender))
goto needs;
else if (has_highbit(value("sender")))
goto needs;
}
if (w & GTO && name_highbit(hp->h_to))
goto needs;
if (w & GCC && name_highbit(hp->h_cc))
goto needs;
if (w & GBCC && name_highbit(hp->h_bcc))
goto needs;
if (w & GSUBJECT && has_highbit(hp->h_subject))
goto needs;
return NULL;
needs: return getcharset(MIME_HIGHBIT);
}
#ifdef HAVE_ICONV
/*
* Convert a string, upper-casing the characters.
*/
static void
uppercopy(char *dest, const char *src)
{
do
*dest++ = upperconv(*src & 0377);
while (*src++);
}
/*
* Strip dashes.
*/
static void
stripdash(char *p)
{
char *q = p;
do
if (*(q = p) != '-')
q++;
while (*p++);
}
/*
* An iconv_open wrapper that tries to convert between character set
* naming conventions.
*/
iconv_t
iconv_open_ft(const char *tocode, const char *fromcode)
{
iconv_t id;
char *t, *f;
/*
* On Linux systems, this call may succeed.
*/
if ((id = iconv_open(tocode, fromcode)) != (iconv_t)-1)
return id;
/*
* Remove the "iso-" prefixes for Solaris.
*/
if (ascncasecmp(tocode, "iso-", 4) == 0)
tocode += 4;
else if (ascncasecmp(tocode, "iso", 3) == 0)
tocode += 3;
if (ascncasecmp(fromcode, "iso-", 4) == 0)
fromcode += 4;
else if (ascncasecmp(fromcode, "iso", 3) == 0)
fromcode += 3;
if (*tocode == '\0' || *fromcode == '\0')
return (iconv_t) -1;
if ((id = iconv_open(tocode, fromcode)) != (iconv_t)-1)
return id;
/*
* Solaris prefers upper-case charset names. Don't ask...
*/
t = salloc(strlen(tocode) + 1);
uppercopy(t, tocode);
f = salloc(strlen(fromcode) + 1);
uppercopy(f, fromcode);
if ((id = iconv_open(t, f)) != (iconv_t)-1)
return id;
/*
* Strip dashes for UnixWare.
*/
stripdash(t);
stripdash(f);
if ((id = iconv_open(t, f)) != (iconv_t)-1)
return id;
/*
* Add your vendor's sillynesses here.
*/
/*
* If the encoding names are equal at this point, they
* are just not understood by iconv(), and we cannot
* sensibly use it in any way. We do not perform this
* as an optimization above since iconv() can otherwise
* be used to check the validity of the input even with
* identical encoding names.
*/
if (strcmp(t, f) == 0)
errno = 0;
return (iconv_t)-1;
}
/*
* Fault-tolerant iconv() function.
*/
static size_t
iconv_ft(iconv_t cd, char **inb, size_t *inbleft, char **outb, size_t *outbleft)
{
size_t sz = 0;
while ((sz = iconv(cd, inb, inbleft, outb, outbleft)) == (size_t)-1
&& (errno == EILSEQ || errno == EINVAL)) {
if (*inbleft > 0) {
(*inb)++;
(*inbleft)--;
} else {
**outb = '\0';
break;
}
if (*outbleft > 0) {
*(*outb)++ = '?';
(*outbleft)--;
} else {
**outb = '\0';
break;
}
}
return sz;
}
/*
* Print an error because of an invalid character sequence.
*/
/*ARGSUSED*/
static void
invalid_seq(int c)
{
/*fprintf(stderr, "iconv: cannot convert %c\n", c);*/
}
#endif /* HAVE_ICONV */
static int
is_this_enc(const char *line, const char *encoding)
{
int quoted = 0, c;
if (*line == '"')
quoted = 1, line++;
while (*line && *encoding)
if (c = *line++, lowerconv(c) != *encoding++)
return 0;
if (quoted && *line == '"')
return 1;
if (*line == '\0' || whitechar(*line & 0377))
return 1;
return 0;
}
/*
* Get the mime encoding from a Content-Transfer-Encoding header field.
*/
enum mimeenc
mime_getenc(char *p)
{
if (is_this_enc(p, "7bit"))
return MIME_7B;
if (is_this_enc(p, "8bit"))
return MIME_8B;
if (is_this_enc(p, "base64"))
return MIME_B64;
if (is_this_enc(p, "binary"))
return MIME_BIN;
if (is_this_enc(p, "quoted-printable"))
return MIME_QP;
return MIME_NONE;
}
/*
* Get the mime content from a Content-Type header field, other parameters
* already stripped.
*/
int
mime_getcontent(char *s)
{
if (strchr(s, '/') == NULL) /* for compatibility with non-MIME */
return MIME_TEXT;
if (asccasecmp(s, "text/plain") == 0)
return MIME_TEXT_PLAIN;
if (asccasecmp(s, "text/html") == 0)
return MIME_TEXT_HTML;
if (ascncasecmp(s, "text/", 5) == 0)
return MIME_TEXT;
if (asccasecmp(s, "message/rfc822") == 0)
return MIME_822;
if (ascncasecmp(s, "message/", 8) == 0)
return MIME_MESSAGE;
if (asccasecmp(s, "multipart/alternative") == 0)
return MIME_ALTERNATIVE;
if (asccasecmp(s, "multipart/digest") == 0)
return MIME_DIGEST;
if (ascncasecmp(s, "multipart/", 10) == 0)
return MIME_MULTI;
if (asccasecmp(s, "application/x-pkcs7-mime") == 0 ||
asccasecmp(s, "application/pkcs7-mime") == 0)
return MIME_PKCS7;
return MIME_UNKNOWN;
}
/*
* Get a mime style parameter from a header line.
*/
char *
mime_getparam(char *param, char *h)
{
char *p = h, *q, *r;
int c;
size_t sz;
sz = strlen(param);
if (!whitechar(*p & 0377)) {
c = '\0';
while (*p && (*p != ';' || c == '\\')) {
c = c == '\\' ? '\0' : *p;
p++;
}
if (*p++ == '\0')
return NULL;
}
for (;;) {
while (whitechar(*p & 0377))
p++;
if (ascncasecmp(p, param, sz) == 0) {
p += sz;
while (whitechar(*p & 0377))
p++;
if (*p++ == '=')
break;
}
c = '\0';
while (*p && (*p != ';' || c == '\\')) {
if (*p == '"' && c != '\\') {
p++;
while (*p && (*p != '"' || c == '\\')) {
c = c == '\\' ? '\0' : *p;
p++;
}
p++;
} else {
c = c == '\\' ? '\0' : *p;
p++;
}
}
if (*p++ == '\0')
return NULL;
}
while (whitechar(*p & 0377))
p++;
q = p;
c = '\0';
if (*p == '"') {
p++;
if ((q = strchr(p, '"')) == NULL)
return NULL;
} else {
q = p;
while (*q && !whitechar(*q & 0377) && *q != ';')
q++;
}
sz = q - p;
r = salloc(q - p + 1);
memcpy(r, p, sz);
*(r + sz) = '\0';
return r;
}
/*
* Get the boundary out of a Content-Type: multipart/xyz header field.
*/
char *
mime_getboundary(char *h)
{
char *p, *q;
size_t sz;
if ((p = mime_getparam("boundary", h)) == NULL)
return NULL;
sz = strlen(p);
q = salloc(sz + 3);
memcpy(q, "--", 2);
memcpy(q + 2, p, sz);
*(q + sz + 2) = '\0';
return q;
}
/*
* Get a line like "text/html html" and look if x matches the extension.
*/
static char *
mime_tline(char *x, char *l)
{
char *type, *n;
int match = 0;
if ((*l & 0200) || alphachar(*l & 0377) == 0)
return NULL;
type = l;
while (blankchar(*l & 0377) == 0 && *l != '\0')
l++;
if (*l == '\0')
return NULL;
*l++ = '\0';
while (blankchar(*l & 0377) != 0 && *l != '\0')
l++;
if (*l == '\0')
return NULL;
while (*l != '\0') {
n = l;
while (whitechar(*l & 0377) == 0 && *l != '\0')
l++;
if (*l != '\0')
*l++ = '\0';
if (strcmp(x, n) == 0) {
match = 1;
break;
}
while (whitechar(*l & 0377) != 0 && *l != '\0')
l++;
}
if (match != 0) {
n = salloc(strlen(type) + 1);
strcpy(n, type);
return n;
}
return NULL;
}
/*
* Check the given MIME type file for extension ext.
*/
static char *
mime_type(char *ext, char *filename)
{
FILE *f;
char *line = NULL;
size_t linesize = 0;
char *type = NULL;
if ((f = Fopen(filename, "r")) == NULL)
return NULL;
while (fgetline(&line, &linesize, NULL, NULL, f, 0)) {
if ((type = mime_tline(ext, line)) != NULL)
break;
}
Fclose(f);
if (line)
free(line);
return type;
}
/*
* Return the Content-Type matching the extension of name.
*/
char *
mime_filecontent(char *name)
{
char *ext, *content;
if ((ext = strrchr(name, '.')) == NULL || *++ext == '\0')
return NULL;
if ((content = mime_type(ext, expand(mimetypes_user))) != NULL)
return content;
if ((content = mime_type(ext, mimetypes_world)) != NULL)
return content;
return NULL;
}
/*
* Check file contents.
*/
static enum mimeclean
mime_isclean(FILE *f)
{
long initial_pos;
unsigned curlen = 1, maxlen = 0, limit = 950;
enum mimeclean isclean = 0;
char *cp;
int c = EOF, lastc;
initial_pos = ftell(f);
do {
lastc = c;
c = getc(f);
curlen++;
if (c == '\n' || c == EOF) {
/*
* RFC 821 imposes a maximum line length of 1000
* characters including the terminating CRLF
* sequence. The configurable limit must not
* exceed that including a safety zone.
*/
if (curlen > maxlen)
maxlen = curlen;
curlen = 1;
} else if (c & 0200) {
isclean |= MIME_HIGHBIT;
} else if (c == '\0') {
isclean |= MIME_HASNUL;
break;
} else if ((c < 040 && (c != '\t' && c != '\f')) || c == 0177) {
isclean |= MIME_CTRLCHAR;
}
} while (c != EOF);
if (lastc != '\n')
isclean |= MIME_NOTERMNL;
clearerr(f);
fseek(f, initial_pos, SEEK_SET);
if ((cp = value("maximum-unencoded-line-length")) != NULL)
limit = atoi(cp);
if (limit < 0 || limit > 950)
limit = 950;
if (maxlen > limit)
isclean |= MIME_LONGLINES;
return isclean;
}
/*
* Get the conversion that matches the encoding specified in the environment.
*/
static enum conversion
gettextconversion(void)
{
char *p;
int convert;
if ((p = value("encoding")) == NULL)
return CONV_8BIT;
if (equal(p, "quoted-printable"))
convert = CONV_TOQP;
else if (equal(p, "8bit"))
convert = CONV_8BIT;
else {
fprintf(stderr, catgets(catd, CATSET, 177,
"Warning: invalid encoding %s, using 8bit\n"), p);
convert = CONV_8BIT;
}
return convert;
}
int
get_mime_convert(FILE *fp, char **contenttype, char **charset,
enum mimeclean *isclean, int dosign)
{
int convert;
*isclean = mime_isclean(fp);
if (*isclean & MIME_HASNUL ||
*contenttype && ascncasecmp(*contenttype, "text/", 5)) {
convert = CONV_TOB64;
if (*contenttype == NULL ||
ascncasecmp(*contenttype, "text/", 5) == 0)
*contenttype = "application/octet-stream";
*charset = NULL;
} else if (*isclean & (MIME_LONGLINES|MIME_CTRLCHAR|MIME_NOTERMNL) ||
dosign)
convert = CONV_TOQP;
else if (*isclean & MIME_HIGHBIT)
convert = gettextconversion();
else
convert = CONV_7BIT;
if (*contenttype == NULL ||
ascncasecmp(*contenttype, "text/", 5) == 0) {
*charset = getcharset(*isclean);
if (wantcharset == (char *)-1) {
*contenttype = "application/octet-stream";
*charset = NULL;
} if (*isclean & MIME_CTRLCHAR) {
convert = CONV_TOB64;
/*
* RFC 2046 forbids control characters other than
* ^I or ^L in text/plain bodies. However, some
* obscure character sets actually contain these
* characters, so the content type can be set.
*/
if ((*contenttype = value("contenttype-cntrl")) == NULL)
*contenttype = "application/octet-stream";
} else if (*contenttype == NULL)
*contenttype = "text/plain";
}
return convert;
}
/*
* Convert c to a hexadecimal character string and store it in hex.
*/
static char *
ctohex(int c, char *hex)
{
unsigned char d;
hex[2] = '\0';
d = c % 16;
hex[1] = basetable[d];
if (c > d)
hex[0] = basetable[(c - d) / 16];
else
hex[0] = basetable[0];
return hex;
}
/*
* Write to a file converting to quoted-printable.
* The mustquote function determines whether a character must be quoted.
*/
static size_t
mime_write_toqp(struct str *in, FILE *fo, int (*mustquote)(int))
{
char *p, *upper, *h, hex[3];
int l;
size_t sz;
sz = in->l;
upper = in->s + in->l;
for (p = in->s, l = 0; p < upper; p++) {
if (mustquote(*p&0377) ||
p < upper-1 && p[1] == '\n' &&
blankchar(p[0]&0377) ||
p < upper-4 && l == 0 &&
p[0] == 'F' && p[1] == 'r' &&
p[2] == 'o' && p[3] == 'm' ||
*p == '.' && l == 0 && p < upper-1 &&
p[1] == '\n') {
if (l >= 69) {
sz += 2;
fwrite("=\n", sizeof (char), 2, fo);
l = 0;
}
sz += 2;
putc('=', fo);
h = ctohex(*p&0377, hex);
fwrite(h, sizeof *h, 2, fo);
l += 3;
} else {
if (*p == '\n')
l = 0;
else if (l >= 71) {
sz += 2;
fwrite("=\n", sizeof (char), 2, fo);
l = 0;
}
putc(*p, fo);
l++;
}
}
return sz;
}
/*
* Write to a stringstruct converting to quoted-printable.
* The mustquote function determines whether a character must be quoted.
*/
static void
mime_str_toqp(struct str *in, struct str *out, int (*mustquote)(int), int inhdr)
{
char *p, *q, *upper;
out->s = smalloc(in->l * 3 + 1);
q = out->s;
out->l = in->l;
upper = in->s + in->l;
for (p = in->s; p < upper; p++) {
if (mustquote(*p&0377) || p+1 < upper && *(p + 1) == '\n' &&
blankchar(*p & 0377)) {
if (inhdr && *p == ' ') {
*q++ = '_';
} else {
out->l += 2;
*q++ = '=';
ctohex(*p&0377, q);
q += 2;
}
} else {
*q++ = *p;
}
}
*q = '\0';
}
/*
* Write to a stringstruct converting from quoted-printable.
*/
static void
mime_fromqp(struct str *in, struct str *out, int ishdr)
{
char *p, *q, *upper;
char quote[4];
out->l = in->l;
out->s = smalloc(out->l + 1);
upper = in->s + in->l;
for (p = in->s, q = out->s; p < upper; p++) {
if (*p == '=') {
do {
p++;
out->l--;
} while (blankchar(*p & 0377) && p < upper);
if (p == upper)
break;
if (*p == '\n') {
out->l--;
continue;
}
if (p + 1 >= upper)
break;
quote[0] = *p++;
quote[1] = *p;
quote[2] = '\0';
*q = (char)strtol(quote, NULL, 16);
q++;
out->l--;
} else if (ishdr && *p == '_')
*q++ = ' ';
else
*q++ = *p;
}
return;
}
#define mime_fromhdr_inc(inc) { \
size_t diff = q - out->s; \
out->s = srealloc(out->s, (maxstor += inc) + 1); \
q = &(out->s)[diff]; \
}
/*
* Convert header fields from RFC 1522 format
*/
void
mime_fromhdr(struct str *in, struct str *out, enum tdflags flags)
{
char *p, *q, *op, *upper, *cs, *cbeg, *tcs, *lastwordend = NULL;
struct str cin, cout;
int convert;
size_t maxstor, lastoutl = 0;
#ifdef HAVE_ICONV
iconv_t fhicd = (iconv_t)-1;
#endif
tcs = gettcharset();
maxstor = in->l;
out->s = smalloc(maxstor + 1);
out->l = 0;
upper = in->s + in->l;
for (p = in->s, q = out->s; p < upper; p++) {
op = p;
if (*p == '=' && *(p + 1) == '?') {
p += 2;
cbeg = p;
while (p < upper && *p != '?')
p++; /* strip charset */
if (p >= upper)
goto notmime;
cs = salloc(++p - cbeg);
memcpy(cs, cbeg, p - cbeg - 1);
cs[p - cbeg - 1] = '\0';
#ifdef HAVE_ICONV
if (fhicd != (iconv_t)-1)
iconv_close(fhicd);