1 files changed, 214 insertions, 0 deletions
diff --git a/debian/patches/upstream/wall-use-fputs_careful.patch b/debian/patches/upstream/wall-use-fputs_careful.patch
new file mode 100644
index 0000000..9bc2738
--- /dev/null
+++ b/debian/patches/upstream/wall-use-fputs_careful.patch
@@ -0,0 +1,214 @@
+From: =?utf-8?b?0L3QsNCx?= <nabijaczleweli@nabijaczleweli.xyz>
+Date: Wed, 15 Mar 2023 16:16:48 +0100
+Subject: wall: use fputs_careful()
+
+LINE_MAX only applies to teletypes in canonical mode: when stdin is a
+file, it could still very much tear; start off at 512 for the sprintf(),
+then use getline() like in write.
+
+The line wrapping has one suboptimal edge-case:
+  $ wall < all
+
+  Broadcast message from nabijaczleweli@tarta (pts/4) (Tue Mar 14 22:31:25
+  2023):
+
+  ^N^O^P^Q^R^S^T^U^V^W^X^Y^Z^[^\^]^^^_
+  !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJ
+  KLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~^?\200\201\202\203\204\205\206
+  \207\210\211\212\213\214\215\216\217\220\221\222\223\224\225\226\227\230\231\232
+  \233\234\235\236\237\240\241\242\243\244\245\246\247\250\251\252\253\254\255\256
+  \257\260\261\262\263\264\265\266\267\270\271\272\273\274\275\276\277\300\301\302
+  \303\304\305\306\307\310\311\312\313\314\315\316\317\320\321\322\323\324\325\326
+  \327\330\331\332\333\334\335\336\337\340\341\342\343\344\345\346\347\350\351\352
+  \353\354\355\356\357\360\361\362\363\364\365\366\367\370\371\372\373\374\375\376
+  \377
+but that's a pathological input, and the result is still infinitely
+better than it was before, so fixing that is more trouble than it's
+worth.
+
+Bug-Debian: https://bugs.debian.org/826596
+---
+ include/carefulputc.h | 42 +++++++++++++++++++++++++++++++++---------
+ login-utils/last.c    |  2 +-
+ term-utils/wall.c     | 38 ++++++--------------------------------
+ term-utils/write.c    |  2 +-
+ 4 files changed, 41 insertions(+), 43 deletions(-)
+
+diff --git a/include/carefulputc.h b/include/carefulputc.h
+index 740add6..3cc6f7f 100644
+--- a/include/carefulputc.h
++++ b/include/carefulputc.h
+@@ -6,6 +6,7 @@
+ #include <ctype.h>
+ #ifdef HAVE_WIDECHAR
+ #include <wctype.h>
++#include <wchar.h>
+ #endif
+ #include <stdbool.h>
+ 
+@@ -15,18 +16,35 @@
+  * A puts() for use in write and wall (that sometimes are sgid tty).
+  * It avoids control and invalid characters.
+  * The locale of the recipient is nominally unknown,
+- * but it's a solid bet that the encoding is compatible with the author's.
++ * but it's a solid bet that it's compatible with the author's.
++ * Use soft_width=0 to disable wrapping.
+  */
+-static inline int fputs_careful(const char * s, FILE *fp, const char ctrl, bool cr_lf)
++static inline int fputs_careful(const char * s, FILE *fp, const char ctrl, bool cr_lf, int soft_width)
+ {
+-	int ret = 0;
++	int ret = 0, col = 0;
+ 
+ 	for (size_t slen = strlen(s); *s; ++s, --slen) {
+-		if (*s == '\n')
++		if (*s == '\t')
++			col += (7 - (col % 8)) - 1;
++		else if (*s == '\r')
++			col = -1;
++		else if (*s == '\a')
++			--col;
++
++		if ((soft_width && col >= soft_width) || *s == '\n') {
++			if (soft_width) {
++				fprintf(fp, "%*s", soft_width - col, "");
++				col = 0;
++			}
+ 			ret = fputs(cr_lf ? "\r\n" : "\n", fp);
+-		else if (isprint(*s) || *s == '\a' || *s == '\t' || *s == '\r')
++			if (*s == '\n' || ret < 0)
++				goto wrote;
++		}
++
++		if (isprint(*s) || *s == '\a' || *s == '\t' || *s == '\r') {
+ 			ret = putc(*s, fp);
+-		else if (!c_isascii(*s)) {
++			++col;
++		} else if (!c_isascii(*s)) {
+ #ifdef HAVE_WIDECHAR
+ 			wchar_t w;
+ 			size_t clen = mbtowc(&w, s, slen);
+@@ -35,21 +53,27 @@ static inline int fputs_careful(const char * s, FILE *fp, const char ctrl, bool
+ 				case (size_t)-1:  // EILSEQ
+ 					mbtowc(NULL, NULL, 0);
+ 				nonprint:
+-					ret = fprintf(fp, "\\%3hho", *s);
++					col += ret = fprintf(fp, "\\%3hho", *s);
+ 					break;
+ 				default:
+ 					if(!iswprint(w))
+ 						goto nonprint;
+ 					ret = fwrite(s, 1, clen, fp);
++					if (soft_width)
++						col += wcwidth(w);
+ 					s += clen - 1;
+ 					slen -= clen - 1;
+ 					break;
+ 			}
+ #else
+-			ret = fprintf(fp, "\\%3hho", *s);
++			col += ret = fprintf(fp, "\\%3hho", *s);
+ #endif
+-		} else
++		} else {
+ 			ret = fputs((char[]){ ctrl, *s ^ 0x40, '\0' }, fp);
++			col += 2;
++		}
++
++	wrote:
+ 		if (ret < 0)
+ 			return EOF;
+ 	}
+diff --git a/login-utils/last.c b/login-utils/last.c
+index 8d08641..b7cd17f 100644
+--- a/login-utils/last.c
++++ b/login-utils/last.c
+@@ -559,7 +559,7 @@ static int list(const struct last_control *ctl, struct utmpx *p, time_t logout_t
+ 	/*
+ 	 *	Print out "final" string safely.
+ 	 */
+-	fputs_careful(final, stdout, '*', false);
++	fputs_careful(final, stdout, '*', false, 0);
+ 
+ 	if (len < 0 || (size_t)len >= sizeof(final))
+ 		putchar('\n');
+diff --git a/term-utils/wall.c b/term-utils/wall.c
+index a51a928..377db45 100644
+--- a/term-utils/wall.c
++++ b/term-utils/wall.c
+@@ -274,29 +274,13 @@ int main(int argc, char **argv)
+ 	exit(EXIT_SUCCESS);
+ }
+ 
+-static void buf_putc_careful(FILE *fs, int c)
+-{
+-	if (isprint(c) || c == '\a' || c == '\t' || c == '\r' || c == '\n')
+-		fputc(c, fs);
+-	else if (!c_isascii(c))
+-		fprintf(fs, "\\%3o", (unsigned char)c);
+-	else
+-		fputs((char[]){ '^', c ^ 0x40, '\0' }, fs);
+-}
+-
+ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		     size_t *mbufsize, int print_banner)
+ {
+-	register int ch, cnt;
+-	char *p, *lbuf, *retbuf;
++	char *lbuf, *retbuf;
+ 	FILE * fs = open_memstream(&retbuf, mbufsize);
+-	long line_max;
+-
+-	line_max = sysconf(_SC_LINE_MAX);
+-	if (line_max <= 0)
+-		line_max = 512;
+-
+-	lbuf = xmalloc(line_max);
++	size_t lbuflen = 512;
++	lbuf = xmalloc(lbuflen);
+ 
+ 	if (print_banner == TRUE) {
+ 		char *hostname = xgethostname();
+@@ -329,7 +313,7 @@ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		   will not overflow as long as %d takes at most 100 chars */
+ 		fprintf(fs, "\r%*s\r\n", TERM_WIDTH, " ");
+ 
+-		snprintf(lbuf, line_max,
++		snprintf(lbuf, lbuflen,
+ 				_("Broadcast message from %s@%s (%s) (%s):"),
+ 				whom, hostname, where, date);
+ 		fprintf(fs, "%-*.*s\007\007\r\n", TERM_WIDTH, TERM_WIDTH, lbuf);
+@@ -373,18 +357,8 @@ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		/*
+ 		 * Read message from stdin.
+ 		 */
+-		while (fgets(lbuf, line_max, stdin)) {
+-			for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) {
+-				if (cnt == TERM_WIDTH || ch == '\n') {
+-					fprintf(fs, "%*s\r\n", TERM_WIDTH - cnt, "");
+-					cnt = 0;
+-				}
+-				if (ch == '\t')
+-					cnt += (7 - (cnt % 8));
+-				if (ch != '\n')
+-					buf_putc_careful(fs, ch);
+-			}
+-		}
++		while (getline(&lbuf, &lbuflen, stdin) >= 0)
++			fputs_careful(lbuf, fs, '^', true, TERM_WIDTH);
+ 	}
+ 	fprintf(fs, "%*s\r\n", TERM_WIDTH, " ");
+ 
+diff --git a/term-utils/write.c b/term-utils/write.c
+index 01c3f35..434b813 100644
+--- a/term-utils/write.c
++++ b/term-utils/write.c
+@@ -276,7 +276,7 @@ static void do_write(const struct write_control *ctl)
+ 		if (signal_received)
+ 			break;
+ 
+-		if (fputs_careful(line, stdout, '^', true) == EOF)
++		if (fputs_careful(line, stdout, '^', true, 0) == EOF)
+ 			err(EXIT_FAILURE, _("carefulputc failed"));
+ 	}
+ 	free(line);