Changeset 698a217

Timestamp:

04/23/06 14:21:02 (15 years ago)

Author:

Perry Lorier <perry@…>

Branches:

4.0.1-hotfixes, cachetimestamps, develop, dpdk-ndag, etsilive, getfragoff, help, libtrace4, master, ndag_format, pfring, rc-4.0.1, rc-4.0.2, rc-4.0.3, rc-4.0.4, ringdecrementfix, ringperformance, ringtimestampfixes

Children:

e4e95499

Parents:

4315572b

Message:

Fix the stdio error handling
Document better the libtraceio API. See the trac wiki for more information.

Location:

lib

Files:

• libtraceio-stdio.c (modified) (4 diffs)
• libtraceio.h (modified) (1 diff)

lib/libtraceio-stdio.c

@@ -5 +5 @@
 #include <stdio.h>
 #include <stdlib.h>
-
-#include <errno.h> /* for debugging */
 
 struct libtrace_io_t {
@@ -17 +15 @@
 
         if (ret==(int)len) {
-                printf("read %i bytes\n",ret);
                 return len;
         }
@@ -23 +20 @@
         /* EOF or an Error occurred */
         if (ferror(io->file)) {
-                int err=errno;
-                perror("fread");
-                errno=err;
                 /* errno will be set */
                 return -1;
         }
-
-        printf("eof\n");
 
         return 0; /* EOF */
@@ -61 +53 @@
 ssize_t libtrace_io_write(libtrace_io_t *io, const void *buf, size_t len)
 {
-        return fwrite(buf,len,1,io->file);
+        int ret=fwrite(buf,1,len,io->file);
+        if (ret==len) {
+                return ret;
+        }
+        
+        /* Error occurred? */
+        if (ferror(io->file))
+                return -1; /* errno will already be set */
+
+        return 0; /* eof */
 }
 

lib/libtraceio.h

@@ -10 +10 @@
 typedef struct libtrace_io_t libtrace_io_t;
 
+/** read a block from a file
+ * @param io    the io file object
+ * @param buf   the buffer to read into
+ * @param len   the number of bytes to read
+ *
+ * @returns -1 on error (with errno set), 0 on eof, otherwise the number of bytes
+ *      read.
+ */
 ssize_t libtrace_io_read(libtrace_io_t *io, void *buf, size_t len);
+/** open a file from a file descriptor (like fdopen(3))
+ * @param fd    file descriptor to read
+ * @param mode  text string to represent what mode to read the file in.
+ *
+ * @returns io object, or NULL on error.
+ */
 libtrace_io_t *libtrace_io_fdopen(int fd, const char *mode);
+/** open a file from a path name
+ * @param path  pathname to read
+ * @param mode  text string to represent what mode to read the file in.
+ *
+ * @returns io object, or NULL on error.
+ */
 libtrace_io_t *libtrace_io_open(const char *path, const char *mode);
+/** close a file and free all of it's resources.
+ * @param io    io object
+ * 
+ * This function doesn't return anything.  In theory it could return an error
+ * but seriously, if it did return an error, what would you do about it?
+ */
 void libtrace_io_close(libtrace_io_t *io);
+
+/** write a block of data to a file
+ * @param io    libtrace io object to write to
+ * @param buf   buffer to write to
+ * @param len   number of bytes to write
+ *
+ * @returns the number of bytes successfully written, or -1 on error with
+ * errno set 
+ */
 ssize_t libtrace_io_write(libtrace_io_t *io, const void *buf, size_t len);
 off_t libtrace_io_seek(libtrace_io_t *io, off_t offset, int whence);