From 6a6807e58750a279d1dad55ce9842bbfa6d946d0 Mon Sep 17 00:00:00 2001
From: Cody Boone Ferguson <53008573+xexyl@users.noreply.github.com>
Date: Tue, 21 Mar 2023 05:58:50 -0700
Subject: [PATCH] Make 1990/tbr alt version that uses fgets not gets

This is so that the warning about gets() is not interspersed with the
initial output of the program (see below). I do want to note that if one
sends EOF it will segfault so to exit one should do ctrl-c (for
instance) (exit never worked). I will look at fixing that fault later on
to match the original code but this is good for now. When fixed (low
priority though) I will consider making the gets() version the alt but
probably not (I guess time will tell).

As for the interspersed output it looks like:

    $ warning: this program uses gets(), which is unsafe.
    # cursor is here

At the cursor I can either hit enter to get another prompt or I can
input a command but this is not immediately obvious.

Updated .gitignore to have tbr.alt.
---
 1990/tbr/.gitignore |  1 +
 1990/tbr/Makefile   |  6 +++---
 1990/tbr/README.md  | 19 ++++++++++++++++++-
 1990/tbr/tbr.alt.c  | 23 +++++++++++++++++++++++
 4 files changed, 45 insertions(+), 4 deletions(-)
 create mode 100644 1990/tbr/tbr.alt.c

diff --git a/1990/tbr/.gitignore b/1990/tbr/.gitignore
index 1e7f77674..68e9c773f 100644
--- a/1990/tbr/.gitignore
+++ b/1990/tbr/.gitignore
@@ -1 +1,2 @@
 tbr
+tbr.alt
diff --git a/1990/tbr/Makefile b/1990/tbr/Makefile
index 2feb9dc3c..f6bdcc07a 100644
--- a/1990/tbr/Makefile
+++ b/1990/tbr/Makefile
@@ -98,7 +98,7 @@ CDEFINE=
 
 # Include files that are needed to compile
 #
-CINCLUDE=
+CINCLUDE= -include stdio.h
 #CINCLUDE= -include stdlib.h
 #CINCLUDE= -include stdio.h
 #CINCLUDE= -include stdlib.h -include stdio.h
@@ -168,8 +168,8 @@ OBJ= ${PROG}.o
 DATA=
 TARGET= ${PROG}
 #
-ALT_OBJ=
-ALT_TARGET=
+ALT_OBJ= ${PROG}.alt.o
+ALT_TARGET= ${PROG}.alt
 
 
 #################
diff --git a/1990/tbr/README.md b/1990/tbr/README.md
index 8fb645eb2..eab1c0f7b 100644
--- a/1990/tbr/README.md
+++ b/1990/tbr/README.md
@@ -22,11 +22,27 @@ modern computers; `exit(3)` returns void but the function was used in a binary
 expression so this would not even compile. Thank you Cody for your assistance!
 
 
+## Alternative code:
+
+Cody also made a version that uses `fgets()` instead of `gets()` so one would
+not get a warning that was interspersed with the output of the initial prompt
+when running the program, to make it both safer and to have a better look. Thank
+you Cody!
+
+To build try:
+
+	make alt
+
+NOTE: it will segfault if you send EOF; to quit send an interrupt like ctrl-c.
+Cody will look at this later.
+
 ## To run:
 
 	./tbr
 	# enter some shell commands
 
+NOTE: globs do not work with this entry. Why?
+
 ## Try:
 
 	./tbr
@@ -37,6 +53,7 @@ expression so this would not even compile. Thank you Cody for your assistance!
 	vi tbr.c
 	# then figure out how to exit vi :-)
 
+What happens if you try using `cd -` to return to previous directory?
 
 ## Judges' comments:
 
@@ -64,7 +81,7 @@ of the program which we include below:
 
 
 
-## Author's comments
+## Author's comments:
 
 Rot13:
 
diff --git a/1990/tbr/tbr.alt.c b/1990/tbr/tbr.alt.c
new file mode 100644
index 000000000..f7bc55d40
--- /dev/null
+++ b/1990/tbr/tbr.alt.c
@@ -0,0 +1,23 @@
+
+#define D ,close(
+
+char              *c,q              [512              ],m[              256
+],*v[           99], **u,        *i[3];int         f[2],p;main       (){for
+ (m[m        [60]=   m[62      ]=32   ]=m[*      m=124   [m]=       9]=6;
+  e(-8)     ,(c=fgets  (q,512,stdin),c[strlen(c)-1]='\0',1)||(exit   (0),0);r(0,0)
+   )for(    ;*++        c;);  }r(t,      o){    *i=i        [2]=    0;for
+     (u=v  +98           ;m[*--c]         ^9;m [*c]          &32  ?i[*c
+       &2]=                *u,u-             v^98              &&++u:
+
+	3	)if(!m[*c]){for(*++c=0;!m[*--c];);
+	*	--u= ++c;}u-v^98?strcmp(*u,"cd")?*c?pipe(f),o=f[
+	1	]:
+	4	,(p=fork())?e(p),o?r(o,0)D o)D*f):
+	1	,wait(0):(o?dup2(*f,0)D*f)D o):*i?
+	5	D 0),e(open(*i,0)):
+	9	,t?dup2(t,1)D t):i[
+	2	]?
+	6	D 1),e(creat(i[2],438)):
+	5	,e(execvp(*u,u))):e(chdir(u[1])*2):
+	3	;}e(x){x<0?write(2,"?\n$ "-x/4,2),x+1||(exit(1),0):
+	5	;}