From 0045ab7c09602708319a4690e555c994887eca97 Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Thu, 10 Apr 2003 21:11:40 +0000
Subject: [PATCH] implement Qungetc and nuke Qgetpos and Qsetpos

---
 include/QF/quakeio.h |  5 +--
 libs/util/quakeio.c  | 88 ++++++++++++++++++++++++++++----------------
 2 files changed, 57 insertions(+), 36 deletions(-)

diff --git a/include/QF/quakeio.h b/include/QF/quakeio.h
index 6f642f278..2b9479d32 100644
--- a/include/QF/quakeio.h
+++ b/include/QF/quakeio.h
@@ -30,8 +30,6 @@
 #ifndef __quakeio_h
 #define __quakeio_h
 
-#include <stdio.h>
-
 typedef struct QFile_s QFile;
 
 void Qexpand_squiggle(const char *path, char *dest);
@@ -49,12 +47,11 @@ int Qputs(QFile *file, const char *buf);
 char *Qgets(QFile *file, char *buf, int count);
 int Qgetc(QFile *file);
 int Qputc(QFile *file, int c);
+int Qungetc (QFile *file, int c);
 int Qseek(QFile *file, long offset, int whence);
 long Qtell(QFile *file);
 int Qflush(QFile *file);
 int Qeof(QFile *file);
 const char *Qgetline(QFile *file);
-int Qgetpos(QFile *file, fpos_t *pos);
-int Qsetpos(QFile *file, fpos_t *pos);
 
 #endif /*__quakeio_h*/
diff --git a/libs/util/quakeio.c b/libs/util/quakeio.c
index 19f590dc0..10db48811 100644
--- a/libs/util/quakeio.c
+++ b/libs/util/quakeio.c
@@ -81,6 +81,7 @@ struct QFile_s {
 #endif
 	off_t size;
 	off_t start;
+	int   c;
 };
 
 
@@ -233,6 +234,7 @@ Qopen (const char *path, const char *mode)
 			return 0;
 		}
 	}
+	file->c = -1;
 	return file;
 }
 
@@ -275,6 +277,7 @@ Qdopen (int fd, const char *mode)
 			return 0;
 		}
 	}
+	file->c = -1;
 	return file;
 }
 
@@ -312,14 +315,26 @@ Qclose (QFile *file)
 int
 Qread (QFile *file, void *buf, int count)
 {
+	int         offs = 0;
+	int         ret;
+
+	if (file->c != -1) {
+		char       *b = buf;
+		*b++ = file->c;
+		buf = b;
+		offs = 1;
+		file->c = -1;
+		count--;
+	}
 	if (file->file)
-		return fread (buf, 1, count, file->file);
-#ifdef HAVE_ZLIB
+		ret = fread (buf, 1, count, file->file);
 	else
-		return gzread (file->gzfile, buf, count);
+#ifdef HAVE_ZLIB
+		ret = gzread (file->gzfile, buf, count);
 #else
-	return -1;
+		return -1;
 #endif
+	return ret == -1 ? ret : ret + offs;
 }
 
 int
@@ -379,19 +394,34 @@ Qputs (QFile *file, const char *buf)
 char *
 Qgets (QFile *file, char *buf, int count)
 {
+	char        *ret = buf;
+
+	if (file->c != -1) {
+		*buf++ = file->c;
+		count--;
+		file->c = -1;
+		if (!count)
+			return ret;
+	}
 	if (file->file)
-		return fgets (buf, count, file->file);
+		buf = fgets (buf, count, file->file);
 #ifdef HAVE_ZLIB
 	else
-		return gzgets (file->gzfile, buf, count);
+		buf = gzgets (file->gzfile, buf, count);
 #else
 	return 0;
 #endif
+	return buf ? ret : 0;
 }
 
 int
 Qgetc (QFile *file)
 {
+	if (file->c != -1) {
+		int         c = file->c;
+		file->c = -1;
+		return c;
+	}
 	if (file->file)
 		return fgetc (file->file);
 #ifdef HAVE_ZLIB
@@ -415,9 +445,18 @@ Qputc (QFile *file, int c)
 #endif
 }
 
+int
+Qungetc (QFile *file, int c)
+{
+	if (file->c == -1)
+		file->c = (byte) c;
+	return c;
+}
+
 int
 Qseek (QFile *file, long offset, int whence)
 {
+	file->c = -1;
 	if (file->file) {
 		int         res;
 		switch (whence) {
@@ -459,14 +498,19 @@ Qseek (QFile *file, long offset, int whence)
 long
 Qtell (QFile *file)
 {
+	int         offs;
+	int         ret;
+
+	offs =  (file->c != -1) ? 1 : 0;
 	if (file->file)
-		return ftell (file->file) - file->start;
-#ifdef HAVE_ZLIB
+		ret = ftell (file->file) - file->start;
 	else
-		return gztell (file->gzfile);	//FIXME does gztell do the right thing?
+#ifdef HAVE_ZLIB
+		ret = gztell (file->gzfile);	//FIXME does gztell do the right thing?
 #else
-	return -1;
+		return -1;
 #endif
+	return ret == -1 ? ret : ret - offs;
 }
 
 int
@@ -485,6 +529,8 @@ Qflush (QFile *file)
 int
 Qeof (QFile *file)
 {
+	if (file->c != -1)
+		return 0;
 	if (file->file)
 		return feof (file->file);
 #ifdef HAVE_ZLIB
@@ -530,25 +576,3 @@ Qgetline (QFile *file)
 	}
 	return buf;
 }
-
-int
-Qgetpos (QFile *file, fpos_t * pos)
-{
-#ifdef HAVE_FPOS_T_STRUCT
-	pos->__pos = Qtell (file);
-	return pos->__pos == -1 ? -1 : 0;
-#else
-	*pos = Qtell (file);
-	return *pos == -1 ? -1 : 0;
-#endif
-}
-
-int
-Qsetpos (QFile *file, fpos_t * pos)
-{
-#ifdef HAVE_FPOS_T_STRUCT
-	return Qseek (file, pos->__pos, 0);
-#else
-	return Qseek (file, *pos, 0);
-#endif
-}