PR 78534, 83704 Handle large formatted I/O

In order to handle large characters when doing formatted I/O, use
size_t and ptrdiff_t for lengths.  Compared to the previous patch,
based on discussions on IRC use size_t for sizes that don't need to be
negative rather than ptrdiff_t everywhere.

Regtested on x86_64-pc-linux-gnu, approved as part of the PR 78534
approval, committed to trunk.

libgfortran/ChangeLog:

2018-01-07  Janne Blomqvist  <jb@gcc.gnu.org>

	PR fortran/78534
	PR fortran/83704
	* io/fbuf.c (fbuf_init): Use size_t instead of int for length.
	(fbuf_debug): Convert debug output to unsigned long.
	(fbuf_reset): Use ptrdiff_t for return value.
	(fbuf_alloc): Use size_t for length argument.
	(fbuf_flush): Handle large buffers.
	(fbuf_flush_list): Likewise.
	(fbuf_seek): Use ptrdiff_t for offset and return value.
	(fbuf_read): Use size_t for length argument.
	(fbuf_getc_refill): Use size_t to match fbuf_read.
	* io/fbuf.h (struct fbuf): Use size_t for lengths.
	(fbuf_init): Use size_t instead of int for length.
	(fbuf_reset): Use ptrdiff_t for return value.
	(fbuf_alloc): Use size_t for length argument.
	(fbuf_seek): Use ptrdiff_t for offset and return value.
	(fbuf_read): Use size_t for length argument.
	* io/io.h (read_block_form): Likewise.
	(read_block_form4): Likewise.
	(write_block): Likewise.
	(read_a): Likewise.
	(read_a_char4): Likewise.
	(read_x): Likewise.
	(write_a): Likewise.
	(write_a_char4): Likewise.
	* io/list_read.c (list_formatted_read_scalar): Use size_t to
	handle large buffers.
	* io/read.c (read_l): Likewise.
	(read_utf8): Likewise.
	(read_utf8_char1): Likewise.
	(read_default_char1): Likewise.
	(read_utf8_char4): Likewise.
	(read_default_char4): Likewise.
	(read_a): Likewise.
	(read_a_char4): Likewise.
	(eat_leading_spaces): Likewise.
	(next_char): Likewise.
	(read_decimal): Likewise.
	(read_radix): Likewise.
	(read_f): Likewise.
	(read_x): Likewise.
	* io/transfer.c (read_sf_internal): Likewise.
	(read_sf): Likewise.
	(read_block_form): Likewise.
	(read_block_form4): Likewise.
	(write_block): Likewise.
	(formatted_transfer_scalar_write): Likewise.
	(next_record_w): Likewise.
	* io/unix.c (mem_alloc_r): Likewise.
	(mem_alloc_r4): Likewise.
	(mem_alloc_w): Likewise.
	(mem_alloc_w4): Likewise.
	(mem_read): Likewise.
	(mem_read4): Likewise.
	(mem_write): Likewise.
	(mem_write4): Likewise.
	(open_internal): Likewise.
	(open_internal4): Likewise.
	* io/unix.h (open_internal): Likewise.
	(open_internal4): Likewise.
	(mem_alloc_w): Likewise.
	(mem_alloc_r): Likewise.
	(mem_alloc_w4): Likewise.
	(mem_alloc_r4): Likewise.
	* io/write.c (write_check_cc): Likewise.
	(write_cc): Likewise.
	(write_a): Likewise.
	(write_a_char4): Likewise.

From-SVN: r256322

1 files changed, 51 insertions, 44 deletions

diff --git a/libgfortran/io/read.c b/libgfortran/io/read.c
index 167587f..87adfb8 100644
--- a/libgfortran/io/read.c
+++ b/libgfortran/io/read.c
@@ -272,7 +272,7 @@ void
 read_l (st_parameter_dt *dtp, const fnode *f, char *dest, int length)
 {
   char *p;
-  int w;
+  size_t w;
 
   w = f->u.w;
 
@@ -316,11 +316,11 @@ read_l (st_parameter_dt *dtp, const fnode *f, char *dest, int length)
 
 
 static gfc_char4_t
-read_utf8 (st_parameter_dt *dtp, int *nbytes) 
+read_utf8 (st_parameter_dt *dtp, size_t *nbytes)
 {
   static const uchar masks[6] = { 0x7F, 0x1F, 0x0F, 0x07, 0x02, 0x01 };
   static const uchar patns[6] = { 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
-  int i, nb, nread;
+  size_t nb, nread;
   gfc_char4_t c;
   char *s;
 
@@ -353,7 +353,7 @@ read_utf8 (st_parameter_dt *dtp, int *nbytes)
   if (s == NULL)
     return 0;
   /* Decode the bytes read.  */
-  for (i = 1; i < nb; i++)
+  for (size_t i = 1; i < nb; i++)
     {
       gfc_char4_t n = *s++;
 
@@ -383,12 +383,11 @@ read_utf8 (st_parameter_dt *dtp, int *nbytes)
 
 
 static void
-read_utf8_char1 (st_parameter_dt *dtp, char *p, int len, int width)
+read_utf8_char1 (st_parameter_dt *dtp, char *p, size_t len, size_t width)
 {
   gfc_char4_t c;
   char *dest;
-  int nbytes;
-  int i, j;
+  size_t nbytes, j;
 
   len = (width < len) ? len : width;
 
@@ -407,16 +406,16 @@ read_utf8_char1 (st_parameter_dt *dtp, char *p, int len, int width)
     }
 
   /* If there was a short read, pad the remaining characters.  */
-  for (i = j; i < len; i++)
+  for (size_t i = j; i < len; i++)
     *dest++ = ' ';
   return;
 }
 
 static void
-read_default_char1 (st_parameter_dt *dtp, char *p, int len, int width)
+read_default_char1 (st_parameter_dt *dtp, char *p, size_t len, size_t width)
 {
   char *s;
-  int m, n;
+  size_t m;
 
   s = read_block_form (dtp, &width);
   
@@ -428,18 +427,16 @@ read_default_char1 (st_parameter_dt *dtp, char *p, int len, int width)
   m = (width > len) ? len : width;
   memcpy (p, s, m);
 
-  n = len - width;
-  if (n > 0)
-    memset (p + m, ' ', n);
+  if (len > width)
+    memset (p + m, ' ', len - width);
 }
 
 
 static void
-read_utf8_char4 (st_parameter_dt *dtp, void *p, int len, int width)
+read_utf8_char4 (st_parameter_dt *dtp, void *p, size_t len, size_t width)
 {
   gfc_char4_t *dest;
-  int nbytes;
-  int i, j;
+  size_t nbytes, j;
 
   len = (width < len) ? len : width;
 
@@ -456,16 +453,16 @@ read_utf8_char4 (st_parameter_dt *dtp, void *p, int len, int width)
     }
 
   /* If there was a short read, pad the remaining characters.  */
-  for (i = j; i < len; i++)
+  for (size_t i = j; i < len; i++)
     *dest++ = (gfc_char4_t) ' ';
   return;
 }
 
 
 static void
-read_default_char4 (st_parameter_dt *dtp, char *p, int len, int width)
+read_default_char4 (st_parameter_dt *dtp, char *p, size_t len, size_t width)
 {
-  int m, n;
+  size_t m, n;
   gfc_char4_t *dest;
 
   if (is_char4_unit(dtp))
@@ -479,15 +476,18 @@ read_default_char4 (st_parameter_dt *dtp, char *p, int len, int width)
       if (width > len)
 	 s4 += (width - len);
 
-      m = ((int) width > len) ? len : (int) width;
+      m = (width > len) ? len : width;
 
       dest = (gfc_char4_t *) p;
 
       for (n = 0; n < m; n++)
 	*dest++ = *s4++;
 
-      for (n = 0; n < len - (int) width; n++)
-	*dest++ = (gfc_char4_t) ' ';
+      if (len > width)
+	{
+	  for (n = 0; n < len - width; n++)
+	    *dest++ = (gfc_char4_t) ' ';
+	}
     }
   else
     {
@@ -500,15 +500,18 @@ read_default_char4 (st_parameter_dt *dtp, char *p, int len, int width)
       if (width > len)
 	 s += (width - len);
 
-      m = ((int) width > len) ? len : (int) width;
+      m = (width > len) ? len : width;
 
       dest = (gfc_char4_t *) p;
 
       for (n = 0; n < m; n++, dest++, s++)
 	*dest = (unsigned char ) *s;
 
-      for (n = 0; n < len - (int) width; n++, dest++)
-	*dest = (unsigned char) ' ';
+      if (len > width)
+	{
+	  for (n = 0; n < len - width; n++, dest++)
+	    *dest = (unsigned char) ' ';
+	}
     }
 }
 
@@ -517,15 +520,14 @@ read_default_char4 (st_parameter_dt *dtp, char *p, int len, int width)
    processing UTF-8 encoding if necessary.  */
 
 void
-read_a (st_parameter_dt *dtp, const fnode *f, char *p, int length)
+read_a (st_parameter_dt *dtp, const fnode *f, char *p, size_t length)
 {
-  int wi;
-  int w;
+  size_t w;
 
-  wi = f->u.w;
-  if (wi == -1) /* '(A)' edit descriptor  */
-    wi = length;
-  w = wi;
+  if (f->u.w == -1) /* '(A)' edit descriptor  */
+    w = length;
+  else
+    w = f->u.w;
 
   /* Read in w characters, treating comma as not a separator.  */
   dtp->u.p.sf_read_comma = 0;
@@ -544,13 +546,14 @@ read_a (st_parameter_dt *dtp, const fnode *f, char *p, int length)
    processing UTF-8 encoding if necessary.  */
 
 void
-read_a_char4 (st_parameter_dt *dtp, const fnode *f, char *p, int length)
+read_a_char4 (st_parameter_dt *dtp, const fnode *f, char *p, size_t length)
 {
-  int w;
+  size_t w;
 
-  w = f->u.w;
-  if (w == -1) /* '(A)' edit descriptor  */
+  if (f->u.w == -1) /* '(A)' edit descriptor  */
     w = length;
+  else
+    w = f->u.w;
 
   /* Read in w characters, treating comma as not a separator.  */
   dtp->u.p.sf_read_comma = 0;
@@ -568,7 +571,7 @@ read_a_char4 (st_parameter_dt *dtp, const fnode *f, char *p, int length)
    ignore the leading spaces.  */
 
 static char *
-eat_leading_spaces (int *width, char *p)
+eat_leading_spaces (size_t *width, char *p)
 {
   for (;;)
     {
@@ -584,7 +587,7 @@ eat_leading_spaces (int *width, char *p)
 
 
 static char
-next_char (st_parameter_dt *dtp, char **p, int *w)
+next_char (st_parameter_dt *dtp, char **p, size_t *w)
 {
   char c, *q;
 
@@ -624,7 +627,8 @@ read_decimal (st_parameter_dt *dtp, const fnode *f, char *dest, int length)
 {
   GFC_UINTEGER_LARGEST value, maxv, maxv_10;
   GFC_INTEGER_LARGEST v;
-  int w, negative; 
+  size_t w;
+  int negative;
   char c, *p;
 
   w = f->u.w;
@@ -732,7 +736,8 @@ read_radix (st_parameter_dt *dtp, const fnode *f, char *dest, int length,
 {
   GFC_UINTEGER_LARGEST value, maxv, maxv_r;
   GFC_INTEGER_LARGEST v;
-  int w, negative;
+  size_t w;
+  int negative;
   char c, *p;
 
   w = f->u.w;
@@ -882,7 +887,8 @@ read_f (st_parameter_dt *dtp, const fnode *f, char *dest, int length)
 #define READF_TMP 50
   char tmp[READF_TMP];
   size_t buf_size = 0;
-  int w, seen_dp, exponent;
+  size_t w;
+  int seen_dp, exponent;
   int exponent_sign;
   const char *p;
   char *buffer;
@@ -1230,12 +1236,13 @@ bad_float:
    and never look at it. */
 
 void
-read_x (st_parameter_dt *dtp, int n)
+read_x (st_parameter_dt *dtp, size_t n)
 {
-  int length, q, q2;
+  size_t length;
+  int q, q2;
 
   if ((dtp->u.p.current_unit->pad_status == PAD_NO || is_internal_unit (dtp))
-       && dtp->u.p.current_unit->bytes_left < n)
+      && dtp->u.p.current_unit->bytes_left < (gfc_offset) n)
     n = dtp->u.p.current_unit->bytes_left;
     
   if (n == 0)