stdio: basic fread/fwrite (WIP)

CMakeLists.txt

@@ -130,10 +130,15 @@ set(SOURCES
   src/libc/stdio/fileutil.c
   src/libc/stdio/fopen.c
   src/libc/stdio/fprintf.c
+  src/libc/stdio/fread.c
   src/libc/stdio/freopen.c
   src/libc/stdio/fseek.c
   src/libc/stdio/fsetpos.c
   src/libc/stdio/ftell.c
+  src/libc/stdio/fwrite.c
+  src/libc/stdio/getc.c
+  src/libc/stdio/getchar.c
+  src/libc/stdio/gets.c
   src/libc/stdio/printf.c
   src/libc/stdio/printf/format_fixed.c
   src/libc/stdio/printf/format_fp.c
@@ -141,6 +146,7 @@ set(SOURCES
   src/libc/stdio/printf/print.c
   src/libc/stdio/printf/util.c
   src/libc/stdio/putc.c
+  src/libc/stdio/putchar.c
   src/libc/stdio/puts.c
   src/libc/stdio/remove.c
   src/libc/stdio/rewind.c

STATUS

@@ -122,16 +122,16 @@ TEST:       Function/symbol/macro needs to be tested
      7.19.7.2  fgets                         TODO
      7.19.7.3  fputc                         TODO
      7.19.7.4  fputs                         TODO
-     7.19.7.5  getc                          TODO
+     7.19.7.5  getc                          LDEPS(fgetc)
-     7.19.7.6  getchar                       TODO
+     7.19.7.6  getchar                       LDEPS(fgetc)
-     7.19.7.7  gets                          TODO
+     7.19.7.7  gets                          LDEPS(fgets)
-     7.19.7.8  putc                          TODO
+     7.19.7.8  putc                          LDPES(fputc)
-     7.19.7.9  putchar                       TODO
+     7.19.7.9  putchar                       LDEPS(fputc)
-     7.19.7.10 puts                          TODO
+     7.19.7.10 puts                          LDEPS(fputs)
      7.19.7.11 ungetc                        TODO
 
-     7.19.8.1  fread                         TODO
+     7.19.8.1  fread                         TEST
-     7.19.8.2  fwrite                        TODO
+     7.19.8.2  fwrite                        TEST
 
      7.19.9.1  fgetpos                       TEST
      7.19.9.2  fseek                         TEST

include/stdio.h

@@ -175,7 +175,60 @@ extern int vasprintf(char ** __restrict__ __str,
 	char const * __restrict__ __format, va_list __args);
 
 /*
-** File positioning functions;
+** Character input/output functions.
+*/
+
+/* Read a character from a stream. */
+extern int fgetc(FILE *__fp);
+
+/* Read at most n characters from a stream, stopping after a newline. */
+extern char *fgets(char * __restrict__ __s, int __n,
+	FILE * __restrict__ __fp);
+
+/* Write a character to a stream. */
+extern int fputc(int __c, FILE *__fp);
+
+/* Write a string to a stream (excluding the NUL nyte). */
+extern int fputs(char const * __restrict__ s, FILE * __restrict__ fp);
+
+extern int getc(FILE *__fp);
+#define getc fgetc
+
+/* Get a character from stdin */
+extern int getchar(void);
+#define getchar() fgetc(stdin)
+
+/* (DEPRECATED; use fgets() instead) Read a string from stdin. */
+extern char *gets(char *__s);
+
+extern int putc(int __c, FILE *__fp);
+#define putc fputc
+
+/* Write a character to stdout */
+extern int putchar(int __c);
+#define putchar(__c) fputc(__c, stdout)
+
+/* Write a string to stdout, followed by a newline */
+extern int puts(char const *__s);
+
+/* Un-read a character back to the stream; only one ungetc() is guaranteed, and
+   the character is lost after reading, writing or flushing. */
+extern int ungetc(int __c, FILE *__fp);
+
+/*
+** Direct input/output functions.
+*/
+
+/* Read an array of items from a stream. */
+extern size_t fread(void * __restrict__ __ptr, size_t __size, size_t __nmemb,
+	FILE * __restrict__ __fp);
+
+/* Write an array of items to a stream. */
+extern size_t fwrite(void const * __restrict__ __ptr, size_t __size,
+	size_t __nmemb, FILE * __restrict__ __fp);
+
+/*
+** File positioning functions.
 */
 
 /* Get current position (same as ftell() unless wide-oriented). */

src/libc/stdio/fflush.c

@@ -14,7 +14,7 @@ int fflush(FILE *fp)
 		return 0;
 
 	/* In reading mode, reset the file offset */
-	if(fp->bufmode == __FILE_BUF_READ && fp->bufpos < fp->bufread) {
+	if(fp->bufdir == __FILE_BUF_READ && fp->bufpos < fp->bufread) {
 		fp->fdpos = fp->fdpos - fp->bufread + fp->bufpos;
 		lseek(fp->fd, fp->fdpos, SEEK_SET);
 		fp->bufpos = 0;
@@ -23,7 +23,7 @@ int fflush(FILE *fp)
 	}
 
 	/* In writing mode, write pending data */
-	if(fp->bufmode == __FILE_BUF_WRITE && fp->bufpos > 0) {
+	if(fp->bufdir == __FILE_BUF_WRITE && fp->bufpos > 0) {
 		ssize_t written = __fp_write(fp, fp->buf, fp->bufpos);
 		fp->bufpos = 0;
 		return (written == (ssize_t)fp->bufpos ? 0 : EOF);

src/libc/stdio/fileutil.c

@@ -1,6 +1,7 @@
 #include "fileutil.h"
 #include <unistd.h>
 #include <stdlib.h>
+#include <string.h>
 #include <errno.h>
 
 int __fp_open(FILE *fp, int fd, bool use_buffering)
@@ -28,6 +29,23 @@ void __fp_close(FILE *fp, bool free_fp)
 		free(fp);
 }
 
+void __fp_buffer_mode_read(FILE *fp)
+{
+	if(fp->buf && fp->bufdir == __FILE_BUF_WRITE && fp->bufpos > 0) {
+		fflush(fp);
+		fp->bufdir = __FILE_BUF_READ;
+	}
+}
+
+void __fp_buffer_mode_write(FILE *fp)
+{
+	if(fp->buf && fp->bufdir == __FILE_BUF_READ
+		&& fp->bufpos < fp->bufread) {
+		fflush(fp);
+		fp->bufdir = __FILE_BUF_WRITE;
+	}
+}
+
 ssize_t __fp_read(FILE *fp, void *data, size_t size)
 {
 	size_t read_ = 0;
@@ -39,8 +57,10 @@ ssize_t __fp_read(FILE *fp, void *data, size_t size)
 			fp->error = 1;
 			return EOF;
 		}
-		if(rc == 0)
+		if(rc == 0) {
+			fp->eof = 1;
 			break;
+		}
 
 		fp->fdpos += rc;
 	}

src/libc/stdio/fileutil.h

@@ -15,6 +15,12 @@ int __fp_open(FILE *fp, int fd, bool use_buffering);
 /* Close fp and free all of its resources. */
 void __fp_close(FILE *fp, bool free_fp);
 
+/* Set reading mode on the buffer. */
+void __fp_buffer_mode_read(FILE *fp);
+
+/* Set writing mode on the buffer. */
+void __fp_buffer_mode_write(FILE *fp);
+
 /* Reads data from a file descriptor; updates the fdpos and sets the error
    indicator. Returns 0 on success, EOF on error. */
 ssize_t __fp_read(FILE *fp, void *data, size_t size);

src/libc/stdio/fread.c

@@ -0,0 +1,45 @@
+#include <stdio.h>
+#include <string.h>
+#include "fileutil.h"
+
+size_t fread(void *data, size_t membsize, size_t nmemb, FILE *fp)
+{
+	size_t size;
+	if(__builtin_umul_overflow(membsize, nmemb, &size)) {
+		fp->error = 1;
+		return 0;
+	}
+
+	if(!fp->buf) {
+		ssize_t rc = __fp_read(fp, data, size);
+		return (rc == EOF) ? 0 : rc;
+	}
+
+	__fp_buffer_mode_read(fp);
+
+	size_t size_read = 0;
+	while(size_read < size) {
+		/* Take what's available in the buffer (may be 0) */
+		size_t size_frag = fp->bufread - fp->bufpos;
+		if(size_frag > size - size_read)
+			size_frag = size - size_read;
+		memcpy(data + size_read, fp->buf + fp->bufpos, size_frag);
+		size_read += size_frag;
+		fp->bufpos += size_frag;
+
+		if(fp->bufpos >= fp->bufread) {
+			fp->bufread = 0;
+			fp->bufpos = 0;
+		}
+		if(size_read >= size)
+			break;
+
+		/* Get more data */
+		ssize_t rc = __fp_read(fp, fp->buf, fp->bufsize);
+		if(rc <= 0) /* EOF or error */
+			break;
+		fp->bufread = rc;
+	}
+
+	return size_read;
+}

src/libc/stdio/fwrite.c

@@ -0,0 +1,42 @@
+#include <stdio.h>
+#include <string.h>
+#include "fileutil.h"
+
+size_t fwrite(void const *data, size_t membsize, size_t nmemb, FILE *fp)
+{
+	size_t size;
+	if(__builtin_umul_overflow(membsize, nmemb, &size)) {
+		fp->error = 1;
+		return 0;
+	}
+
+	if(!fp->buf) {
+		ssize_t rc = __fp_write(fp, data, size);
+		return (rc == EOF) ? 0 : rc;
+	}
+
+	__fp_buffer_mode_write(fp);
+
+	// TODO: fwrite: line buffering
+
+	size_t size_written = 0;
+	while(size_written < size) {
+		/* Fill the buffer */
+		size_t size_frag = fp->bufsize - fp->bufpos;
+		if(size_frag > size - size_written)
+			size_frag = size - size_written;
+
+		memcpy(fp->buf + fp->bufpos, data + size_written, size_frag);
+		size_written += size_frag;
+		fp->bufpos += size_frag;
+
+		if(fp->bufpos >= fp->bufsize) {
+			ssize_t rc = __fp_write(fp, fp->buf, fp->bufpos);
+			if(rc <= 0) /* error */
+				break;
+			fp->bufpos = 0;
+		}
+	}
+
+	return size_written;
+}

src/libc/stdio/getc.c

@@ -0,0 +1,7 @@
+#include <stdio.h>
+#undef getc
+
+int getc(FILE *fp)
+{
+	return fgetc(fp);
+}

src/libc/stdio/getchar.c

@@ -0,0 +1,7 @@
+#include <stdio.h>
+#undef getchar
+
+int getchar(void)
+{
+	return fgetc(stdin);
+}

src/libc/stdio/gets.c

@@ -0,0 +1,7 @@
+#include <stdio.h>
+#include <limits.h>
+
+extern char *gets(char *s)
+{
+	return fgets(s, INT_MAX, stdin);
+}

src/libc/stdio/putc.c

@@ -1,11 +1,7 @@
 #include <stdio.h>
-#include <unistd.h>
+#undef putc
 
-int putchar(int c)
+int putc(int c, FILE *fp)
 {
-	char n;
+	return fputc(c, fp);
-
-	n = (char)c;
-	write(STDOUT_FILENO, &n, 1);
-	return (n);
 }

src/libc/stdio/putchar.c

@@ -0,0 +1,7 @@
+#include <stdio.h>
+#undef putchar
+
+int putchar(int c)
+{
+	return fputc(c, stdout);
+}

src/libc/stdio/puts.c

@@ -1,18 +1,11 @@
 #include <stdio.h>
-#include <string.h>
-#include <unistd.h>
 
-/*
+int puts(char const *s)
-** puts() writes the string s and a trailing newline to stdout.
-** FIXME: check last write error !
-*/
-int puts(const char *s)
 {
-	size_t size;
+	int rc = 0;
-	size_t n;
+	if(fputs(s, stdout) != 0)
-
+		rc = -1;
-	size = strlen(s);
+	if(fputc('\n', stdout) == EOF)
-	n = write(STDOUT_FILENO, s, size);
+		rc = -1;
-	write(STDOUT_FILENO, "\n", 1);
+	return rc;
-	return (-(n == size));
 }