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-rw-r--r--boehm-gc/include/ec.h70
1 files changed, 70 insertions, 0 deletions
diff --git a/boehm-gc/include/ec.h b/boehm-gc/include/ec.h
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+++ b/boehm-gc/include/ec.h
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+# ifndef EC_H
+# define EC_H
+
+# ifndef CORD_H
+# include "cord.h"
+# endif
+
+/* Extensible cords are strings that may be destructively appended to. */
+/* They allow fast construction of cords from characters that are */
+/* being read from a stream. */
+/*
+ * A client might look like:
+ *
+ * {
+ * CORD_ec x;
+ * CORD result;
+ * char c;
+ * FILE *f;
+ *
+ * ...
+ * CORD_ec_init(x);
+ * while(...) {
+ * c = getc(f);
+ * ...
+ * CORD_ec_append(x, c);
+ * }
+ * result = CORD_balance(CORD_ec_to_cord(x));
+ *
+ * If a C string is desired as the final result, the call to CORD_balance
+ * may be replaced by a call to CORD_to_char_star.
+ */
+
+# ifndef CORD_BUFSZ
+# define CORD_BUFSZ 128
+# endif
+
+typedef struct CORD_ec_struct {
+ CORD ec_cord;
+ char * ec_bufptr;
+ char ec_buf[CORD_BUFSZ+1];
+} CORD_ec[1];
+
+/* This structure represents the concatenation of ec_cord with */
+/* ec_buf[0 ... (ec_bufptr-ec_buf-1)] */
+
+/* Flush the buffer part of the extended chord into ec_cord. */
+/* Note that this is almost the only real function, and it is */
+/* implemented in 6 lines in cordxtra.c */
+void CORD_ec_flush_buf(CORD_ec x);
+
+/* Convert an extensible cord to a cord. */
+# define CORD_ec_to_cord(x) (CORD_ec_flush_buf(x), (x)[0].ec_cord)
+
+/* Initialize an extensible cord. */
+# define CORD_ec_init(x) ((x)[0].ec_cord = 0, (x)[0].ec_bufptr = (x)[0].ec_buf)
+
+/* Append a character to an extensible cord. */
+# define CORD_ec_append(x, c) \
+ { \
+ if ((x)[0].ec_bufptr == (x)[0].ec_buf + CORD_BUFSZ) { \
+ CORD_ec_flush_buf(x); \
+ } \
+ *((x)[0].ec_bufptr)++ = (c); \
+ }
+
+/* Append a cord to an extensible cord. Structure remains shared with */
+/* original. */
+void CORD_ec_append_cord(CORD_ec x, CORD s);
+
+# endif /* EC_H */