Bug 697110: Ensure stream 'file_limit' is correct

Follow-on from commit 4b101952d81a5899972f81f7b18ef3becd5bd45e

There are several places that set, and check the value of file_limit for
streams. Ensure they all use the requisite value whether the gs_offset_t is
64 bit (normal) or 32 bit (abnormal).

To make it easier, and more consistent, pull the logic out into a macro.

7 files changed, 18 insertions, 16 deletions

diff --git a/base/gsioram.c b/base/gsioram.c
index 9bf57c038..44805ac14 100644
--- a/base/gsioram.c
+++ b/base/gsioram.c
@@ -207,7 +207,7 @@ sread_ram(register stream * s, ramhandle * file, byte * buf, uint len)
     s->file_modes = s->modes;
     s->file_offset = 0;
     /* XXX get a more sensible number from the fs? */
-    s->file_limit = max_long;
+    s->file_limit = S_FILE_LIMIT_MAX;
 }
 
 /* Procedures for reading from a file */
@@ -268,7 +268,7 @@ s_ram_read_process(stream_state * st, stream_cursor_read * ignore_pr,
     int status = 1;
     int count;
 
-    if (s->file_limit < max_long) {
+    if (s->file_limit < S_FILE_LIMIT_MAX) {
     long limit_count = s->file_offset + s->file_limit -
     ramfile_tell(file);
 
@@ -298,7 +298,7 @@ swrite_ram(register stream * s, ramhandle * file, byte * buf, uint len)
     s->file = (FILE*)file;
     s->file_modes = s->modes;
     s->file_offset = 0;        /* in case we switch to reading later */
-    s->file_limit = max_long;    /* ibid. */
+    s->file_limit = S_FILE_LIMIT_MAX;
 }
 
 /* Initialize for appending to a file. */
diff --git a/base/gsiorom.c b/base/gsiorom.c
index 92864b25b..a897d72e5 100644
--- a/base/gsiorom.c
+++ b/base/gsiorom.c
@@ -114,7 +114,7 @@ sread_block(register stream *s,  const byte *ptr, uint len, const uint32_t *node
     s->file = (FILE *)node;	/* convenient place to put it for %rom% files */
     s->file_modes = s->modes;
     s->file_offset = 0;
-    s->file_limit = max_long;
+    s->file_limit = S_FILE_LIMIT_MAX;
 }
 
 /* Return the number of available bytes */
@@ -193,7 +193,7 @@ s_block_read_process(stream_state * st, stream_cursor_read * ignore_pr,
 
     if (s->position + (s->cursor.r.limit - s->cbuf + 1) >= filelen || block_data == NULL)
         return EOFC;			/* at EOF */
-    if (s->file_limit < max_long) {
+    if (s->file_limit < S_FILE_LIMIT_MAX) {
         /* Adjust count for subfile limit */
         uint32_t limit_count = s->file_offset + s->file_limit - s->position;
 
diff --git a/base/sfxfd.c b/base/sfxfd.c
index 185c0753b..e0bb3f878 100644
--- a/base/sfxfd.c
+++ b/base/sfxfd.c
@@ -128,7 +128,7 @@ sread_fileno(register stream * s, FILE * file, byte * buf, uint len)
     s->file = file;
     s->file_modes = s->modes;
     s->file_offset = 0;
-    s->file_limit = max_long;
+    s->file_limit = S_FILE_LIMIT_MAX;
 }
 
 /* Confine reading to a subfile.  This is primarily for reusable streams. */
@@ -141,7 +141,7 @@ int
 sread_subfile(stream *s, gs_offset_t start, gs_offset_t length)
 {
     if (s->file == 0 || s->modes != s_mode_read + s_mode_seek ||
-        s->file_offset != 0 || s->file_limit != max_long ||
+        s->file_offset != 0 || s->file_limit != S_FILE_LIMIT_MAX ||
         ((s->position < start || s->position > start + length) &&
          sseek(s, start) < 0)
         )
@@ -226,7 +226,7 @@ s_fileno_read_process(stream_state * st, stream_cursor_read * ignore_pr,
 again:
     max_count = pw->limit - pw->ptr;
     status = 1;
-    if (s->file_limit < max_long) {
+    if (s->file_limit < S_FILE_LIMIT_MAX) {
         gs_offset_t limit_count = s->file_offset + s->file_limit - ltell(fd);
 
         if (max_count > limit_count)
@@ -269,7 +269,7 @@ swrite_fileno(register stream * s, FILE * file, byte * buf, uint len)
     s->file = file;
     s->file_modes = s->modes;
     s->file_offset = 0;		/* in case we switch to reading later */
-    s->file_limit = max_long;	/* ibid. */
+    s->file_limit = S_FILE_LIMIT_MAX;
 }
 /* Initialize for appending to an OS file. */
 void
diff --git a/base/sfxstdio.c b/base/sfxstdio.c
index d6e48f448..0d901107d 100644
--- a/base/sfxstdio.c
+++ b/base/sfxstdio.c
@@ -79,7 +79,7 @@ sread_subfile(stream *s, gs_offset_t start, gs_offset_t length)
 {
     if (s->file == 0 || s->modes != s_mode_read + s_mode_seek ||
         s->file_offset != 0 ||
-        s->file_limit != (sizeof(gs_offset_t) > 4 ? max_int64_t : max_long) ||
+        s->file_limit != S_FILE_LIMIT_MAX ||
         ((s->position < start || s->position > start + length) && sseek(s, start) < 0)
         )
         return ERRC;
@@ -161,7 +161,7 @@ s_file_read_process(stream_state * st, stream_cursor_read * ignore_pr,
     int status = 1;
     int count;
 
-    if (s->file_limit < max_long) {
+    if (s->file_limit < S_FILE_LIMIT_MAX) {
         gs_offset_t limit_count = s->file_offset + s->file_limit - gp_ftell_64(file);
 
         if (max_count > limit_count)
@@ -193,7 +193,7 @@ swrite_file(register stream * s, FILE * file, byte * buf, uint len)
     s->file = file;
     s->file_modes = s->modes;
     s->file_offset = 0;		/* in case we switch to reading later */
-    s->file_limit = (sizeof(gs_offset_t) > 4 ? max_int64_t : max_long);	/* ibid. */
+    s->file_limit = S_FILE_LIMIT_MAX;
 }
 /* Initialize for appending to an OS file. */
 void
diff --git a/base/stream.h b/base/stream.h
index 4097d20c2..d13a23605 100644
--- a/base/stream.h
+++ b/base/stream.h
@@ -190,6 +190,8 @@ extern_st(st_stream);
     stream_enum_ptrs, stream_reloc_ptrs, stream_finalize)
 #define STREAM_NUM_PTRS 6
 
+#define S_FILE_LIMIT_MAX (sizeof(gs_offset_t) > 4 ? max_int64_t : max_long)
+
 /* Initialize the checking IDs of a stream. */
 #define s_init_ids(s) ((s)->read_id = (s)->write_id = 1)
 #define s_init_read_id(s) ((s)->read_id = 1, (s)->write_id = 0)
diff --git a/psi/zfrsd.c b/psi/zfrsd.c
index 69aa0cc95..191107d8a 100644
--- a/psi/zfrsd.c
+++ b/psi/zfrsd.c
@@ -370,7 +370,7 @@ make_aos(i_ctx_t *i_ctx_p, os_ptr op, int blk_sz, int blk_sz_last, uint file_sz)
     s_std_init(s, buf, aos_buf_size, &s_aos_procs, s_mode_read + s_mode_seek);
     s->state = (stream_state *)ss;
     s->file_offset = 0;
-    s->file_limit = max_long;
+    s->file_limit = S_FILE_LIMIT_MAX;
     s->close_at_eod = false;
     s->read_id = 1;
     make_stream_file(op, s, "r");
diff --git a/psi/ziodevsc.c b/psi/ziodevsc.c
index 835848f29..6dd744f13 100644
--- a/psi/ziodevsc.c
+++ b/psi/ziodevsc.c
@@ -143,7 +143,7 @@ stdin_open(gx_io_device * iodev, const char *access, stream ** ps,
         s->file = 0;
         s->file_modes = s->modes;
         s->file_offset = 0;
-        s->file_limit = max_long;
+        s->file_limit = S_FILE_LIMIT_MAX;
         s->save_close = s_std_null;
         make_file(&ref_stdin, a_readonly | avm_system, s->read_id, s);
         *ps = s;
@@ -220,7 +220,7 @@ stdout_open(gx_io_device * iodev, const char *access, stream ** ps,
         s->file = 0;
         s->file_modes = s->modes;
         s->file_offset = 0;		/* in case we switch to reading later */
-        s->file_limit = max_long;	/* ibid. */
+        s->file_limit = S_FILE_LIMIT_MAX;
         s->save_close = s->procs.flush;
         make_file(&ref_stdout, a_write | avm_system, s->write_id, s);
         *ps = s;
@@ -291,7 +291,7 @@ stderr_open(gx_io_device * iodev, const char *access, stream ** ps,
         s->file = 0;
         s->file_modes = s->modes;
         s->file_offset = 0;		/* in case we switch to reading later */
-        s->file_limit = max_long;	/* ibid. */
+        s->file_limit = S_FILE_LIMIT_MAX;
         s->save_close = s->procs.flush;
         make_file(&ref_stderr, a_write | avm_system, s->write_id, s);
         *ps = s;