From: Karel Zak <kzak@redhat.com>
Date: Mon, 29 May 2023 13:10:24 +0000 (+0200)
Subject: lib/ttyutils: add get_terminal_default_type()
X-Git-Tag: v2.40-rc1~419^2~3
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=cba97be9fb9e5376c338c19de7d8267f055813e7;p=thirdparty%2Futil-linux.git

lib/ttyutils: add get_terminal_default_type()

Based on code from agetty.

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/include/ttyutils.h b/include/ttyutils.h
index e28a2b03bf..39182b66bb 100644
--- a/include/ttyutils.h
+++ b/include/ttyutils.h
@@ -88,6 +88,7 @@ struct chardata {
 extern int get_terminal_dimension(int *cols, int *lines);
 extern int get_terminal_width(int default_width);
 extern int get_terminal_type(const char **type);
+extern char *get_terminal_default_type(const char *ttyname, int is_serial);
 extern int get_terminal_stdfd(void);
 extern int get_terminal_name(const char **path, const char **name,
 			     const char **number);
diff --git a/lib/ttyutils.c b/lib/ttyutils.c
index 7064565039..7c8860e63b 100644
--- a/lib/ttyutils.c
+++ b/lib/ttyutils.c
@@ -7,9 +7,40 @@
 #include <ctype.h>
 #include <unistd.h>
 
+#ifdef HAVE_GETTTYNAM
+# include <ttyent.h>
+#endif
+
 #include "c.h"
 #include "ttyutils.h"
 
+#ifdef __linux__
+#  ifndef DEFAULT_VCTERM
+#    define DEFAULT_VCTERM "linux"
+#  endif
+#  if defined (__s390__) || defined (__s390x__)
+#    define DEFAULT_TTYS0  "dumb"
+#    define DEFAULT_TTY32  "ibm327x"
+#    define DEFAULT_TTYS1  "vt220"
+#  endif
+#  ifndef DEFAULT_STERM
+#    define DEFAULT_STERM  "vt102"
+#  endif
+#elif defined(__GNU__)
+#  ifndef DEFAULT_VCTERM
+#    define DEFAULT_VCTERM "hurd"
+#  endif
+#  ifndef DEFAULT_STERM
+#    define DEFAULT_STERM  "vt102"
+#  endif
+#else
+#  ifndef DEFAULT_VCTERM
+#    define DEFAULT_VCTERM "vt100"
+#  endif
+#  ifndef DEFAULT_STERM
+#    define DEFAULT_STERM  "vt100"
+#  endif
+#endif
 
 static int get_env_int(const char *name)
 {
@@ -130,6 +161,37 @@ int get_terminal_type(const char **type)
 	return 0;
 }
 
+char *get_terminal_default_type(const char *ttyname, int is_serial)
+{
+#ifdef HAVE_GETTTYNAM
+	if (ttyname) {
+		struct ttyent *ent = getttynam(ttyname);
+
+		if (ent && ent->ty_type)
+			return strdup(ent->ty_type);
+	}
+#endif
+
+#if defined (__s390__) || defined (__s390x__)
+	if (ttyname) {
+		/*
+		 * Special terminal on first serial line on a S/390(x) which
+		 * is due legacy reasons a block terminal of type 3270 or
+		 * higher.  Whereas the second serial line on a S/390(x) is
+		 * a real character terminal which is compatible with VT220.
+		 */
+		if (strcmp(ttyname, "ttyS0") == 0)		/* linux/drivers/s390/char/con3215.c */
+			return strdup(DEFAULT_TTYS0);
+		else if (strncmp(ttyname, "3270/tty", 8) == 0)	/* linux/drivers/s390/char/con3270.c */
+			return strdup(DEFAULT_TTY32);
+		else if (strcmp(ttyname, "ttyS1") == 0)		/* linux/drivers/s390/char/sclp_vt220.c */
+			return strdup(DEFAULT_TTYS1);
+	}
+#endif
+
+	return strdup(is_serial ? DEFAULT_STERM : DEFAULT_VCTERM);
+}
+
 #ifdef TEST_PROGRAM_TTYUTILS
 # include <stdlib.h>
 int main(void)
@@ -138,13 +200,21 @@ int main(void)
 	int c, l;
 
 	if (get_terminal_name(&path, &name, &num) == 0) {
-		fprintf(stderr, "tty path:   %s\n", path);
-		fprintf(stderr, "tty name:   %s\n", name);
-		fprintf(stderr, "tty number: %s\n", num);
+		char *term;
+
+		fprintf(stderr, "tty path:      %s\n", path);
+		fprintf(stderr, "tty name:      %s\n", name);
+		fprintf(stderr, "tty number:    %s\n", num);
+
+		fprintf(stderr, "tty term:      %s\n", getenv("TERM"));
+
+		term = get_terminal_default_type(name, 0);
+		fprintf(stderr, "tty dflt term: %s\n", term);
+		free(term);
 	}
 	get_terminal_dimension(&c, &l);
-	fprintf(stderr,         "tty cols:   %d\n", c);
-	fprintf(stderr,         "tty lines:  %d\n", l);
+	fprintf(stderr,         "tty cols:      %d\n", c);
+	fprintf(stderr,         "tty lines:     %d\n", l);
 
 
 	return EXIT_SUCCESS;