Re: pmap: German umlauts are shown as question marks

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On 2024/11/05 11:53:33 +0100, Dr. Werner Fink wrote:
> On 2024/11/05 09:23:16 +0100, Daniel Hofstetter wrote:
> > Hi,
> >=20
> > I noticed that if I have a binary with German umlauts, the umlauts are
> > shown correctly in the first line but not in the memory map. There,
> > they are shown as question marks:
> >=20
> > $ pmap 19508
> > 19508:   ./target/debug/hello_=C3=A4=C3=B6=C3=BC
> > 00005db66dc51000     20K r---- hello_??????
> > 00005db66dc56000    264K r-x-- hello_??????
> > 00005db66dc98000     52K r---- hello_??????
> > 00005db66dca5000     12K r---- hello_??????
> > 00005db66dca8000      4K rw--- hello_??????
>=20
> There are two places where isprint(3) is checking the bytes of the remain=
ing
> path in /proc/<pid>/maps ... UTF-8 encoding are multibyte characters means
> such multibyte characters are mapped to `?' for each byte.
>=20

A dirty hack for checking for (multi)byte characters with mblen(3)
=2E.. strlen(3) usage could be optimized indeed.

--=20
  "Having a smoking section in a restaurant is like having
          a peeing section in a swimming pool." -- Edward Burr

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--- src/pmap.c
+++ src/pmap.c	2024-11-05 12:04:25.265048972 +0000
@@ -199,9 +199,13 @@ static void discover_shm_minor(void)
 			*tmp =3D '\0';
 		tmp =3D mapbuf_b;
 		while (*tmp) {
-			if (!isprint(*tmp))
+			int n =3D mblen(tmp, strlen(tmp));
+			if (n < 0) {
 				*tmp =3D '?';
-			tmp++;
+				tmp++;
+			} else {
+				tmp +=3D n;
+			}
 		}
 		if (start > (unsigned long)addr)
 			continue;
@@ -684,9 +688,13 @@ static int one_proc (struct pids_stack *
 			*tmp =3D '\0';
 		tmp =3D mapbuf;
 		while (*tmp) {
-			if (!isprint(*tmp))
+			int n =3D mblen(tmp, strlen(tmp));
+			if (n < 0) {
 				*tmp =3D '?';
-			tmp++;
+				tmp++;
+			} else {
+				tmp +=3D n;
+			}
 		}
=20
 		diff =3D end - start_To_Avoid_Warning;

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