1 files changed, 374 insertions, 0 deletions
diff --git a/lib/str_decode.c b/lib/str_decode.c
new file mode 100644
index 0000000..d2c2ab4
--- /dev/null
+++ b/lib/str_decode.c
@@ -0,0 +1,374 @@
+/*-------------------------------------------------------*/
+/* lib/str_decode.c	( NTHU CS MapleBBS Ver 3.00 )	 */
+/*-------------------------------------------------------*/
+/* target : included C for QP/BASE64 decoding		 */
+/* create : 95/03/29				 	 */
+/* update : 97/03/29				 	 */
+/*-------------------------------------------------------*/
+
+
+/* ----------------------------------------------------- */
+/* QP code : "0123456789ABCDEF"				 */
+/* ----------------------------------------------------- */
+
+
+static int
+qp_code(x)
+  register int x;
+{
+  if (x >= '0' && x <= '9')
+    return x - '0';
+  if (x >= 'a' && x <= 'f')
+    return x - 'a' + 10;
+  if (x >= 'A' && x <= 'F')
+    return x - 'A' + 10;
+  return -1;
+}
+
+
+/* ------------------------------------------------------------------ */
+/* BASE64 :							      */
+/* "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/" */
+/* ------------------------------------------------------------------ */
+
+
+static int
+base64_code(x)
+  register int x;
+{
+  if (x >= 'A' && x <= 'Z')
+    return x - 'A';
+  if (x >= 'a' && x <= 'z')
+    return x - 'a' + 26;
+  if (x >= '0' && x <= '9')
+    return x - '0' + 52;
+  if (x == '+')
+    return 62;
+  if (x == '/')
+    return 63;
+  return -1;
+}
+
+
+/* ----------------------------------------------------- */
+/* �� encode / charset					 */
+/* ----------------------------------------------------- */
+
+
+static inline int
+isreturn(c)
+  unsigned char c;
+{
+  return c == '\r' || c == '\n';
+}
+
+
+static inline int 
+isspace(c)
+  unsigned char c;
+{
+  return c == ' ' || c == '\t' || isreturn(c);
+}
+
+
+/* ��Content-Transfer-Encode ���Ĥ@�Ӧr��, �̷Ӽзǥu�i��O q,b,7,8 �o�|�� */
+char *
+mm_getencode(str, code)
+  unsigned char *str;
+  char *code;
+{
+  if (str)
+  {
+    /* skip leading space */
+    while (isspace(*str))
+      str++;
+
+    if (!str_ncmp(str, "quoted-printable", 16))
+    {
+      *code = 'q';
+      return str + 16;
+    }
+    if (!str_ncmp(str, "base64", 6))
+    {
+      *code = 'b';
+      return str + 6;
+    }
+  }
+
+  *code = 0;
+  return str;
+}
+
+
+/* �� charset */
+void
+mm_getcharset(str, charset, size)
+  const char *str;
+  char *charset;
+  int size;		/* charset size */
+{
+  char *ptr, delim;
+  int i;
+
+  *charset = '\0';
+
+  if (!str)
+    return;
+
+  if (!(ptr = (char *) strstr(str, "charset=")))
+    return;
+
+  ptr += 8;
+  delim = '\0';
+  i = 0;
+  size--;	/* �O�d�Ŷ��� '\0' */
+
+  for (; *ptr && *ptr != delim && !isspace(*ptr); ptr++)
+  {
+    if (*ptr == '\"')
+    {
+      delim = *ptr;
+      continue;
+    }
+
+    charset[i] = *ptr;
+    if (++i >= size)
+      break;
+  }
+  charset[i] = '\0';
+
+  if (!str_cmp(charset, "iso-8859-1"))	/* ���v�]�񤣥i�� */
+    *charset = '\0';
+}
+
+
+/* ----------------------------------------------------- */
+/* judge & decode QP / BASE64				 */
+/* ----------------------------------------------------- */
+
+
+/* PaulLiu.030410: 
+   RFC 2047 (Header) QP �����A�̭��W�w '_' ���� ' ' (US_ASCII���ť�)
+   �� RFC 2045 (Body) QP �����A'_' �٬O '_'�A�S���S���γ~
+   �ҥH�b�� mmdecode ���G���g
+*/
+
+static int
+mmdecode_header(src, encode, dst)	/* �� Header �� mmdecode */
+  unsigned char *src;		/* Thor.980901: src�Mdst�i�ۦP, ��src�@�w��?��\0���� */
+  unsigned char encode;		/* Thor.980901: �`�N, decode�X�����G���|�ۤv�[�W \0 */
+  unsigned char *dst;
+{
+  unsigned char *t;
+  int pattern, bits;
+  int ch;
+
+  t = dst;
+  encode |= 0x20;		/* Thor: to lower */
+
+  switch (encode)
+  {
+  case 'q':			/* Thor: quoted-printable */
+
+    while ((ch = *src) && ch != '?')	/* Thor: Header �̭� 0 �M '?' ���O delimiter */
+    {
+      if (ch == '=')
+      {
+	int x, y;
+
+	x = *++src;
+	y = x ? *++src : 0;
+	if (isreturn(x))
+	  continue;
+
+	if ((x = qp_code(x)) < 0 || (y = qp_code(y)) < 0)
+	  return -1;
+
+	*t++ = (x << 4) + y;
+      }
+      else if (ch == '_')	/* Header �n�� '_' ���� ' ' */
+      {
+	*t++ = ' ';
+      }
+      else
+      {
+	*t++ = ch;
+      }
+      src++;
+    }
+    return t - dst;
+
+  case 'b':			/* Thor: base 64 */
+
+    /* Thor: pattern & bits are cleared outside while() */
+    pattern = 0;
+    bits = 0;
+
+    while ((ch = *src) && ch != '?')	/* Thor: Header �̭� 0 �M '?' ���O delimiter */
+    {
+      int x;
+
+      x = base64_code(*src++);
+      if (x < 0)		/* Thor: ignore everything not in the base64,=,.. */
+	continue;
+
+      pattern = (pattern << 6) | x;
+      bits += 6;		/* Thor: 1 code gains 6 bits */
+      if (bits >= 8)		/* Thor: enough to form a byte */
+      {
+	bits -= 8;
+	*t++ = (pattern >> bits) & 0xff;
+      }
+    }
+    return t - dst;
+  }
+
+  return -1;
+}
+
+
+int
+mmdecode(src, encode, dst)	/* �� Header �� mmdecode */
+  unsigned char *src;		/* Thor.980901: src�Mdst�i�ۦP, ��src�@�w��?��\0���� */
+  unsigned char encode;		/* Thor.980901: �`�N, decode�X�����G���|�ۤv�[�W \0 */
+  unsigned char *dst;
+{
+  unsigned char *t;
+  int pattern, bits;
+  int ch;
+
+  t = dst;
+  encode |= 0x20;		/* Thor: to lower */
+
+  switch (encode)
+  {
+  case 'q':			/* Thor: quoted-printable */
+
+    while (ch = *src)		/* Thor: 0 �O delimiter */
+    {
+      if (ch == '=')
+      {
+	int x, y;
+
+	x = *++src;
+	y = x ? *++src : 0;
+	if (isreturn(x))
+	  continue;
+
+	if ((x = qp_code(x)) < 0 || (y = qp_code(y)) < 0)
+	  return -1;
+
+	*t++ = (x << 4) + y;
+      }
+      else
+      {
+	*t++ = ch;
+      }
+      src++;
+    }
+    return t - dst;
+
+  case 'b':			/* Thor: base 64 */
+
+    /* Thor: pattern & bits are cleared outside while() */
+    pattern = 0;
+    bits = 0;
+
+    while (ch = *src)		/* Thor: 0 �O delimiter */
+    {
+      int x;
+
+      x = base64_code(*src++);
+      if (x < 0)		/* Thor: ignore everything not in the base64,=,.. */
+	continue;
+
+      pattern = (pattern << 6) | x;
+      bits += 6;		/* Thor: 1 code gains 6 bits */
+      if (bits >= 8)		/* Thor: enough to form a byte */
+      {
+	bits -= 8;
+	*t++ = (pattern >> bits) & 0xff;
+      }
+    }
+    return t - dst;
+  }
+
+  return -1;
+}
+
+
+void
+str_decode(str)
+  unsigned char *str;
+{
+  int adj;
+  unsigned char *src, *dst;
+  unsigned char buf[512];
+
+  src = str;
+  dst = buf;
+  adj = 0;
+
+  while (*src && (dst - buf) < sizeof(buf) - 1)
+  {
+    if (*src != '=')
+    {				/* Thor: not coded */
+      unsigned char *tmp = src;
+      while (adj && *tmp && isspace(*tmp))
+	tmp++;
+      if (adj && *tmp == '=')
+      {				/* Thor: jump over space */
+	adj = 0;
+	src = tmp;
+      }
+      else
+	*dst++ = *src++;
+    }
+    else			/* Thor: *src == '=' */
+    {
+      unsigned char *tmp = src + 1;
+      if (*tmp == '?')		/* Thor: =? coded */
+      {
+	/* "=?%s?Q?" for QP, "=?%s?B?" for BASE64 */
+	tmp++;
+	while (*tmp && *tmp != '?')
+	  tmp++;
+	if (*tmp && tmp[1] && tmp[2] == '?')	/* Thor: *tmp == '?' */
+	{
+	  int i = mmdecode_header(tmp + 3, tmp[1], dst);
+	  if (i >= 0)
+	  {
+	    tmp += 3;		/* Thor: decode's src */
+	    while (*tmp && *tmp++ != '?');	/* Thor: no ? end, mmdecode_header -1 */
+	    /* Thor.980901: 0 �]�� decode ���� */
+	    if (*tmp == '=')
+	      tmp++;
+	    src = tmp;		/* Thor: decode over */
+	    dst += i;
+	    adj = 1;		/* Thor: adjcent */
+	  }
+	}
+      }
+
+      while (src != tmp)	/* Thor: not coded */
+	*dst++ = *src++;
+    }
+  }
+  *dst = 0;
+  strcpy(str, buf);
+}
+
+
+#if 0
+int
+main()
+{
+  char buf[1024] = "=?Big5?B?pl7C0CA6IFtNYXBsZUJCU11UbyB5dW5sdW5nKDE4SzRGTE0pIFtWQUxJ?=\n\t=?Big5?B?RF0=?=";
+
+  str_decode(buf);
+  puts(buf);
+
+  buf[mmdecode("=A7=DA=A4@=AA=BD=B8I=A4=A3=A8=EC=A7=DA=BE=C7=AA=F8", 'q', buf)] = '\0';
+  puts(buf);
+}
+#endif