[2/4] tui-disasm: Fix line buffer size calculation
Commit Message
The code that fills the TUI disassembly window content first calculates
the maximum full length of a displayed disassembly line. This
calculation typically yields the wrong result. The result is too large,
so the bug does not cause any run-time failures, but unnecessary
confusion for the reader. This patch fixes the calculation.
gdb/ChangeLog:
* tui/tui-disasm.c (tui_set_disassem_content): Fix calculation of
the longest disassembly line's length.
---
gdb/tui/tui-disasm.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)
Comments
On 11/08/2016 06:56 PM, Andreas Arnez wrote:
> The code that fills the TUI disassembly window content first calculates
> the maximum full length of a displayed disassembly line. This
> calculation typically yields the wrong result. The result is too large,
> so the bug does not cause any run-time failures, but unnecessary
> confusion for the reader. This patch fixes the calculation.
>
> gdb/ChangeLog:
>
> * tui/tui-disasm.c (tui_set_disassem_content): Fix calculation of
> the longest disassembly line's length.
OK.
Thanks,
Pedro Alves
@@ -178,7 +178,7 @@ tui_set_disassem_content (struct gdbarch *gdbarch, CORE_ADDR pc)
int tab_len = tui_default_tab_len ();
struct tui_asm_line *asm_lines;
int insn_pos;
- int addr_size, max_size;
+ int addr_size, insn_size;
char *line;
if (pc == 0)
@@ -203,9 +203,9 @@ tui_set_disassem_content (struct gdbarch *gdbarch, CORE_ADDR pc)
tui_disassemble (gdbarch, asm_lines, pc, max_lines);
- /* See what is the maximum length of an address and of a line. */
+ /* Determine maximum address- and instruction lengths. */
addr_size = 0;
- max_size = 0;
+ insn_size = 0;
for (i = 0; i < max_lines; i++)
{
size_t len = strlen (asm_lines[i].addr_string);
@@ -213,16 +213,17 @@ tui_set_disassem_content (struct gdbarch *gdbarch, CORE_ADDR pc)
if (len > addr_size)
addr_size = len;
- len = strlen (asm_lines[i].insn) + tab_len;
- if (len > max_size)
- max_size = len;
+ len = strlen (asm_lines[i].insn);
+ if (len > insn_size)
+ insn_size = len;
}
- max_size += addr_size + tab_len;
- /* Allocate memory to create each line. */
- line = (char*) alloca (max_size);
+ /* Align instructions to the same column. */
insn_pos = (1 + (addr_size / tab_len)) * tab_len;
+ /* Allocate memory to create each line. */
+ line = (char*) alloca (insn_pos + insn_size + 1);
+
/* Now construct each line. */
for (i = 0; i < max_lines; i++)
{