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<p>Hello,</p>
<p>thanks for the patch! LGTM</p>
<p>Sergey</p>
<div class="moz-cite-prefix">On 7/21/26 10:59, Sergey Kaplun wrote:<br>
</div>
<blockquote type="cite"
cite="mid:20260721075939.2894880-1-skaplun@tarantool.org">
<pre wrap="" class="moz-quote-pre">From: Mike Pall <mike>
Reported by Magnus Wibeck.
(cherry picked from commit d508715ab657261e8437a52c1b1966c20ab1631d)
In LuaJIT the second `<a class="moz-txt-link-freetext" href="fp:seek()">fp:seek()</a>` argument (offset) doesn't coerce from a
string to an integer value, unlike PUC-Rio Lua 5.1 does.
This patch adds missing coercion.
Sergey Kaplun:
* added the description and the test for the problem
Part of tarantool/tarantool#12880
---
Branch: <a class="moz-txt-link-freetext" href="https://github.com/tarantool/luajit/tree/skaplun/lj-1343-fseek-offset-coercion">https://github.com/tarantool/luajit/tree/skaplun/lj-1343-fseek-offset-coercion</a>
Related issues:
* <a class="moz-txt-link-freetext" href="https://github.com/LuaJIT/LuaJIT/issues/1343">https://github.com/LuaJIT/LuaJIT/issues/1343</a>
* <a class="moz-txt-link-freetext" href="https://github.com/tarantool/tarantool/issues/12880">https://github.com/tarantool/tarantool/issues/12880</a>
src/Makefile.dep.original | 2 +-
src/lib_io.c | 4 +++-
.../lj-1343-fseek-offset-coercion.test.lua | 23 +++++++++++++++++++
3 files changed, 27 insertions(+), 2 deletions(-)
create mode 100644 test/tarantool-tests/lj-1343-fseek-offset-coercion.test.lua
diff --git a/src/Makefile.dep.original b/src/Makefile.dep.original
index 436685f5..acc6b3ba 100644
--- a/src/Makefile.dep.original
+++ b/src/Makefile.dep.original
@@ -21,7 +21,7 @@ lib_ffi.o: lib_ffi.c lua.h luaconf.h lauxlib.h lualib.h lj_obj.h lj_def.h \
lib_init.o: lib_init.c lua.h luaconf.h lauxlib.h lualib.h lmisclib.h lj_arch.h
lib_io.o: lib_io.c lua.h luaconf.h lauxlib.h lualib.h lj_obj.h lj_def.h \
lj_arch.h lj_gc.h lj_err.h lj_errmsg.h lj_buf.h lj_str.h lj_state.h \
- lj_strfmt.h lj_ff.h lj_ffdef.h lj_lib.h lj_libdef.h
+ lj_strfmt.h lj_ff.h lj_ffdef.h lj_lib.h lj_strscan.h lj_libdef.h
lib_jit.o: lib_jit.c lua.h luaconf.h lauxlib.h lualib.h lj_obj.h lj_def.h \
lj_arch.h lj_gc.h lj_err.h lj_errmsg.h lj_debug.h lj_str.h lj_tab.h \
lj_state.h lj_bc.h lj_ctype.h lj_ir.h lj_jit.h lj_ircall.h lj_iropt.h \
diff --git a/src/lib_io.c b/src/lib_io.c
index ef39e535..2d0abf78 100644
--- a/src/lib_io.c
+++ b/src/lib_io.c
@@ -25,6 +25,7 @@
#include "lj_strfmt.h"
#include "lj_ff.h"
#include "lj_lib.h"
+#include "lj_strscan.h"
/* Userdata payload for I/O file. */
typedef struct IOFileUD {
@@ -317,13 +318,14 @@ LJLIB_CF(io_method_seek)
FILE *fp = io_tofile(L)->fp;
int opt = lj_lib_checkopt(L, 2, 1, "\3set\3cur\3end");
int64_t ofs = 0;
- cTValue *o;
+ TValue *o;
int res;
if (opt == 0) opt = SEEK_SET;
else if (opt == 1) opt = SEEK_CUR;
else if (opt == 2) opt = SEEK_END;
o = L->base+2;
if (o < L->top) {
+ if (tvisstr(o)) lj_strscan_num(strV(o), o);
if (tvisint(o))
ofs = (int64_t)intV(o);
else if (tvisnum(o))
diff --git a/test/tarantool-tests/lj-1343-fseek-offset-coercion.test.lua b/test/tarantool-tests/lj-1343-fseek-offset-coercion.test.lua
new file mode 100644
index 00000000..fdfc6ce5
--- /dev/null
+++ b/test/tarantool-tests/lj-1343-fseek-offset-coercion.test.lua
@@ -0,0 +1,23 @@
+local tap = require('tap')
+
+-- The test file to demonstrate LuaJIT's missing coercion for the
+-- `io.fseek()` offset argument.
+-- See also: <a class="moz-txt-link-freetext" href="https://github.com/LuaJIT/LuaJIT/issues/1343">https://github.com/LuaJIT/LuaJIT/issues/1343</a>.
+
+local test = tap.test('lj-1343-fseek-offset-coercion')
+
+test:plan(2)
+
+local f = io.tmpfile()
+
+f:write('12345')
+
+f:seek('set', 0)
+f:seek('set', '1')
+test:is(<a class="moz-txt-link-freetext" href="f:read('*all')">f:read('*all')</a>, '2345', 'base coercion test')
+
+f:seek('set', 0)
+f:seek('set', '1.9')
+test:is(<a class="moz-txt-link-freetext" href="f:read('*all')">f:read('*all')</a>, '2345', 'coercion test for non-integer value')
+
+test:done(true)
</pre>
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