#define BYTEWIDTH 8
-#ifndef SIGN_EXTEND_CHAR
-#define SIGN_EXTEND_CHAR(x) (x)
+/* We remove any previous definition of `SIGN_EXTEND_CHAR',
+ since ours (we hope) works properly with all combinations of
+ machines, compilers, `char' and `unsigned char' argument types.
+ (Per Bothner suggested the basic approach.) */
+#undef SIGN_EXTEND_CHAR
+#if __STDC__
+#define SIGN_EXTEND_CHAR(c) ((signed char) (c))
+#else /* not __STDC__ */
+/* As in Harbison and Steele. */
+#define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
#endif
\f
static int obscure_syntax = 0;
#define PATUNFETCH p--
-#define EXTEND_BUFFER \
- { char *old_buffer = bufp->buffer; \
- if (bufp->allocated == (1<<16)) goto too_big; \
- bufp->allocated *= 2; \
- if (bufp->allocated > (1<<16)) bufp->allocated = (1<<16); \
- if (!(bufp->buffer = (char *) realloc (bufp->buffer, bufp->allocated))) \
- goto memory_exhausted; \
- c = bufp->buffer - old_buffer; \
- b += c; \
- if (fixup_jump) \
- fixup_jump += c; \
- if (laststart) \
- laststart += c; \
- begalt += c; \
- if (pending_exact) \
- pending_exact += c; \
- }
+/* This is not an arbitrary limit: the arguments which represent offsets
+ into the pattern are two bytes long. So if 2^16 bytes turns out to
+ be too small, many things would have to change. */
+#define MAX_BUF_SIZE (1 << 16)
+
+
+/* Extend the buffer by twice its current size via realloc and
+ reset the pointers that pointed into the old block to point to the
+ correct places in the new one. If extending the buffer results in it
+ being larger than MAX_BUF_SIZE, then flag memory exhausted. */
+#define EXTEND_BUFFER \
+ do { \
+ char *old_buffer = bufp->buffer; \
+ if (bufp->allocated == MAX_BUF_SIZE) \
+ goto too_big; \
+ bufp->allocated <<= 1; \
+ if (bufp->allocated > MAX_BUF_SIZE) \
+ bufp->allocated = MAX_BUF_SIZE; \
+ bufp->buffer = (char *) realloc (bufp->buffer, bufp->allocated);\
+ if (bufp->buffer == NULL) \
+ goto memory_exhausted; \
+ /* If the buffer moved, move all the pointers into it. */ \
+ if (old_buffer != bufp->buffer) \
+ { \
+ b = (b - old_buffer) + bufp->buffer; \
+ begalt = (begalt - old_buffer) + bufp->buffer; \
+ if (fixup_jump) \
+ fixup_jump = (fixup_jump - old_buffer) + bufp->buffer;\
+ if (laststart) \
+ laststart = (laststart - old_buffer) + bufp->buffer; \
+ if (pending_exact) \
+ pending_exact = (pending_exact - old_buffer) + bufp->buffer; \
+ } \
+ } while (0)
static void store_jump (), insert_jump ();