Initial commit

1 files changed, 70 insertions, 0 deletions

diff --git a/sys/libc/cread.c b/sys/libc/cread.c
new file mode 100644
index 00000000..8cc727a5
--- /dev/null
+++ b/sys/libc/cread.c
@@ -0,0 +1,70 @@
+/* Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+*/
+
+#define import_spp
+#define	import_libc
+#define	import_xnames
+#define import_stdio
+#define import_error
+#define import_fset
+#include <iraf.h>
+
+
+/* C_READ -- FIO read from a file.  Read up to maxbytes bytes from the stream
+** fd into the buffer buf.  If the device associated with file fd is a record
+** structured device a single record is read, and the byte count will generally
+** be less than the maximum.  If the physical record was larger than maxbytes
+** the remainder of the record is returned in successive reads.  If the actual
+** file is a text file FIO XCHARs are returned as C chars.  If the actual file
+** is a binary file no conversion is performed, and an integral number of XCHARs
+** are read.
+**
+** For reasons of consistency with SPP usage, EOF is returned when end of file
+** is reached (fread returns 0), and an error action is taken if a file read
+** error occurs.  We cannot return ERR when an error occurs since ERR and EOF
+** have the same value in STDIO land.  IFERR may be used to catch file read
+** errors.
+*/
+int
+c_read (
+  XINT	fd,			/* FIO file descriptor		*/
+  char	*buf,			/* output buffer		*/
+  int	maxbytes		/* max bytes to read		*/
+)
+{
+	XINT  x_fd = fd;
+	int   nchars_read;
+
+
+	if (c_fstati (fd, F_TYPE) == TEXT_FILE) {
+	    register char	*op = buf;
+	    register int	ch, n = maxbytes;
+	    register FILE	*fp = FDTOFP(fd);
+
+	    while (--n >= 0 && (ch = getc(fp)) >= 0) {
+		*op++ = ch;
+		if (ch == '\n')
+		    break;
+	    }
+	    if (ferror (fp))
+		c_erract (EA_ERROR);
+	    if (!(nchars_read = op - buf))
+		nchars_read = XEOF;
+
+	} else {
+	    XINT	x_maxchars = maxbytes / sizeof(XCHAR);
+	    XCHAR	*bp = (XCHAR *)buf;
+
+	    /* Verify that the pointer coercion char->XCHAR->char is legal,
+	     * i.e., that the char pointer is aligned to an XCHAR word
+	     * boundary if required on this machine.
+	     */
+	    if (buf != (char *)bp)
+		c_error (1, "c_read: buffer not xchar aligned");
+	    
+	    if ((nchars_read = READ (&x_fd, bp, &x_maxchars)) > 0)
+		nchars_read *= sizeof(XCHAR);
+	}
+
+	return (nchars_read == XEOF ? EOF : nchars_read);
+}