12 files changed, 129 insertions, 57 deletions

diff --git a/shell/Config.src b/shell/Config.src
index 5efbf9995..5b3fe08f3 100644
--- a/shell/Config.src
+++ b/shell/Config.src
@@ -166,9 +166,10 @@ config FEATURE_SH_HISTFILESIZE
         default y
         depends on SHELL_ASH || SHELL_HUSH
         help
-        This option makes busybox shells to use $HISTFILESIZE variable
-        to set shell history size. Note that its max value is capped
-        by "History size" setting in library tuning section.
+        This option makes busybox shells to use $HISTSIZE and
+        $HISTFILESIZE variables to set shell history size.
+        Note that its max value is capped by "History size" setting
+        in library tuning section.
 
 config FEATURE_SH_EMBEDDED_SCRIPTS
         bool "Embed scripts in the binary"
diff --git a/shell/ash.c b/shell/ash.c
index 99fbf6053..0038aa1e9 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -4275,7 +4275,7 @@ signal_handler(int signo)
                         return;
         }
 #if ENABLE_FEATURE_EDITING
-        bb_got_signal = signo; /* for read_line_input: "we got a signal" */
+        bb_got_signal = signo; /* for read_line_input / read builtin: "we got a signal" */
 #endif
         gotsig[signo - 1] = 1;
         pending_sig = signo;
@@ -15821,6 +15821,11 @@ readcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
                 if (pending_sig == 0)
                         goto again;
         }
+
+        if ((uintptr_t)r == 2) /* -t SEC timeout? */
+                /* bash: "The exit status is greater than 128 if the timeout is exceeded." */
+                /* The actual value observed with bash 5.2.15: */
+                return 128 + SIGALRM;
 #else /* ENABLE_PLATFORM_MINGW32 */
         if ((uintptr_t)r == 2) {
                 /* Timeout, return 128 + SIGALRM */
@@ -15973,8 +15978,25 @@ exitshell(void)
         char *p;
 
 #if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
-        save_history(line_input_state); /* may be NULL */
+        if (line_input_state) {
+                const char *hp;
+# if ENABLE_FEATURE_SH_HISTFILESIZE
+// in bash:
+// HISTFILESIZE controls the on-disk history file size (in lines, 0=no history):
+// "When this variable is assigned a value, the history file is truncated, if necessary"
+// but we do it only at exit, not on assignment:
+                /* Use HISTFILESIZE to limit file size */
+                hp = lookupvar("HISTFILESIZE");
+                if (hp)
+                        line_input_state->max_history = size_from_HISTFILESIZE(hp);
+# endif
+                /* HISTFILE: "If unset, the command history is not saved when a shell exits." */
+                hp = lookupvar("HISTFILE");
+                line_input_state->hist_file = hp;
+                save_history(line_input_state); /* no-op if hist_file is NULL or "" */
+        }
 #endif
+
         savestatus = exitstatus;
         TRACE(("pid %d, exitshell(%d)\n", getpid(), savestatus));
         if (setjmp(loc.loc))
@@ -16478,7 +16500,12 @@ int ash_main(int argc UNUSED_PARAM, char **argv)
                         if (hp)
                                 line_input_state->hist_file = xstrdup(hp);
 # if ENABLE_FEATURE_SH_HISTFILESIZE
-                        hp = lookupvar("HISTFILESIZE");
+                        hp = lookupvar("HISTSIZE");
+                        /* Using HISTFILESIZE above to limit max_history would be WRONG:
+                         * users may set HISTFILESIZE=0 in their profile scripts
+                         * to prevent _saving_ of history files, but still want to have
+                         * non-zero history limit for in-memory list.
+                         */
                         line_input_state->max_history = size_from_HISTFILESIZE(hp);
 # endif
                 }
diff --git a/shell/ash_test/ash-read/read_ifs2.right b/shell/ash_test/ash-read/read_ifs2.right
new file mode 100644
index 000000000..797137dae
--- /dev/null
+++ b/shell/ash_test/ash-read/read_ifs2.right
@@ -0,0 +1,9 @@
+|X|Y:Z:|
+|X|Y:Z|
+|X|Y|
+|X|Y|
+|X||
+|X||
+|||
+Whitespace should be trimmed too:
+|X|Y|
diff --git a/shell/ash_test/ash-read/read_ifs2.tests b/shell/ash_test/ash-read/read_ifs2.tests
new file mode 100755
index 000000000..f01a68978
--- /dev/null
+++ b/shell/ash_test/ash-read/read_ifs2.tests
@@ -0,0 +1,9 @@
+echo "X:Y:Z:" | (IFS=": " read x y; echo "|$x|$y|")
+echo "X:Y:Z"  | (IFS=": " read x y; echo "|$x|$y|")
+echo "X:Y:"   | (IFS=": " read x y; echo "|$x|$y|")
+echo "X:Y"    | (IFS=": " read x y; echo "|$x|$y|")
+echo "X:"     | (IFS=": " read x y; echo "|$x|$y|")
+echo "X"      | (IFS=": " read x y; echo "|$x|$y|")
+echo ""       | (IFS=": " read x y; echo "|$x|$y|")
+echo Whitespace should be trimmed too:
+echo "X:Y  : " | (IFS=": " read x y; echo "|$x|$y|")
diff --git a/shell/ash_test/ash-read/read_t.right b/shell/ash_test/ash-read/read_t.right
index 04126cbe6..3eedae275 100644
--- a/shell/ash_test/ash-read/read_t.right
+++ b/shell/ash_test/ash-read/read_t.right
@@ -1,4 +1,4 @@
-><
-><
->test<
->test<
+>te:142<
+>:142<
+>test:0<
+>test:0<
diff --git a/shell/ash_test/ash-read/read_t.tests b/shell/ash_test/ash-read/read_t.tests
index d65f1aeaa..9fbeec517 100755
--- a/shell/ash_test/ash-read/read_t.tests
+++ b/shell/ash_test/ash-read/read_t.tests
@@ -1,10 +1,10 @@
-# bash 3.2 outputs:
+# bash 5.2 outputs:
 
-# ><
-{ echo -n 'te'; sleep 2; echo 'st'; }   | (read -t 1 reply; echo ">$reply<")
-# ><
-{               sleep 2; echo 'test'; } | (read -t 1 reply; echo ">$reply<")
-# >test<
-{ echo -n 'te'; sleep 1; echo 'st'; }   | (read -t 2 reply; echo ">$reply<")
-# >test<
-{               sleep 1; echo 'test'; } | (read -t 2 reply; echo ">$reply<")
+# >te:142<
+{ echo -n 'te'; sleep 2; echo 'st'; }   | (read -t 1 reply; echo ">$reply:$?<")
+# >:142<
+{               sleep 2; echo 'test'; } | (read -t 1 reply; echo ">$reply:$?<")
+# >test:0<
+{ echo -n 'te'; sleep 1; echo 'st'; }   | (read -t 2 reply; echo ">$reply:$?<")
+# >test:0<
+{               sleep 1; echo 'test'; } | (read -t 2 reply; echo ">$reply:$?<")
diff --git a/shell/ash_test/printenv.c b/shell/ash_test/printenv.c
index c86308d3b..f0f41984d 100644
--- a/shell/ash_test/printenv.c
+++ b/shell/ash_test/printenv.c
@@ -31,9 +31,7 @@
 extern char **environ;
 
 int
-main (argc, argv)
-     int argc;
-     char **argv;
+main (int argc, char **argv)
 {
   register char **envp, *eval;
   int len;
diff --git a/shell/ash_test/recho.c b/shell/ash_test/recho.c
index 42a5feafd..7e96b14cc 100644
--- a/shell/ash_test/recho.c
+++ b/shell/ash_test/recho.c
@@ -27,7 +27,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-void strprint();
+void strprint(char *);
 
 int main(int argc, char **argv)
 {
diff --git a/shell/hush.c b/shell/hush.c
index 4a97293cc..0b2bc01f5 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -1973,7 +1973,7 @@ static void record_pending_signo(int sig)
          || (G_traps && G_traps[SIGCHLD] && G_traps[SIGCHLD][0])
          /* ^^^ if SIGCHLD, interrupt line reading only if it has a trap */
         ) {
-                bb_got_signal = sig; /* for read_line_input: "we got a signal" */
+                bb_got_signal = sig; /* for read_line_input / read builtin: "we got a signal" */
         }
 #endif
 #if ENABLE_HUSH_FAST
@@ -2099,11 +2099,29 @@ static sighandler_t pick_sighandler(unsigned sig)
         return handler;
 }
 
+static const char* FAST_FUNC get_local_var_value(const char *name);
+
 /* Restores tty foreground process group, and exits. */
 static void hush_exit(int exitcode)
 {
 #if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
-        save_history(G.line_input_state); /* may be NULL */
+        if (G.line_input_state) {
+                const char *hp;
+# if ENABLE_FEATURE_SH_HISTFILESIZE
+// in bash:
+// HISTFILESIZE controls the on-disk history file size (in lines, 0=no history):
+// "When this variable is assigned a value, the history file is truncated, if necessary"
+// but we do it only at exit, not on every assignment:
+                /* Use HISTFILESIZE to limit file size */
+                hp = get_local_var_value("HISTFILESIZE");
+                if (hp)
+                        G.line_input_state->max_history = size_from_HISTFILESIZE(hp);
+# endif
+                /* HISTFILE: "If unset, the command history is not saved when a shell exits." */
+                hp = get_local_var_value("HISTFILE");
+                G.line_input_state->hist_file = hp;
+                save_history(G.line_input_state); /* no-op if hist_file is NULL or "" */
+        }
 #endif
 
         fflush_all();
@@ -10427,7 +10445,7 @@ int hush_main(int argc, char **argv)
         if (!get_local_var_value("PATH"))
                 set_local_var_from_halves("PATH", bb_default_root_path);
 
-        /* PS1/PS2 are set later, if we determine that we are interactive */
+        /* PS1/PS2/HISTFILE are set later, if we determine that we are interactive */
 
         /* bash also exports SHLVL and _,
          * and sets (but doesn't export) the following variables:
@@ -10449,7 +10467,6 @@ int hush_main(int argc, char **argv)
          * BASH_SOURCE=()
          * DIRSTACK=()
          * PIPESTATUS=([0]="0")
-         * HISTFILE=/<xxx>/.bash_history
          * HISTFILESIZE=500
          * HISTSIZE=500
          * MAILCHECK=60
@@ -10809,18 +10826,30 @@ int hush_main(int argc, char **argv)
                         const char *hp = get_local_var_value("HISTFILE");
                         if (!hp) {
                                 hp = get_local_var_value("HOME");
-                                if (hp)
+                                if (hp) {
                                         hp = concat_path_file(hp, ".hush_history");
+                                        /* Make HISTFILE set on exit (else history won't be saved) */
+                                        set_local_var_from_halves("HISTFILE", hp);
+                                }
                         } else {
                                 hp = xstrdup(hp);
                         }
                         if (hp) {
                                 G.line_input_state->hist_file = hp;
-                                //set_local_var(xasprintf("HISTFILE=%s", ...));
                         }
 #  if ENABLE_FEATURE_SH_HISTFILESIZE
-                        hp = get_local_var_value("HISTFILESIZE");
+                        hp = get_local_var_value("HISTSIZE");
+                        /* Using HISTFILESIZE above to limit max_history would be WRONG:
+                         * users may set HISTFILESIZE=0 in their profile scripts
+                         * to prevent _saving_ of history files, but still want to have
+                         * non-zero history limit for in-memory list.
+                         */
+// in bash, runtime history size is controlled by HISTSIZE (0=no history),
+// HISTFILESIZE controls on-disk history file size (in lines, 0=no history):
                         G.line_input_state->max_history = size_from_HISTFILESIZE(hp);
+// HISTFILESIZE: "The shell sets the default value to the value of HISTSIZE after reading any startup files."
+// HISTSIZE: "The shell sets the default value to 500 after reading any startup files."
+// (meaning: if the value wasn't set after startup files, the default value is set as described above)
 #  endif
                 }
 # endif
@@ -11175,6 +11204,11 @@ static int FAST_FUNC builtin_read(char **argv)
                         goto again;
         }
 
+        if ((uintptr_t)r == 2) /* -t SEC timeout? */
+                /* bash: "The exit status is greater than 128 if the timeout is exceeded." */
+                /* The actual value observed with bash 5.2.15: */
+                return 128 + SIGALRM;
+
         if ((uintptr_t)r > 1) {
                 bb_simple_error_msg(r);
                 r = (char*)(uintptr_t)1;
diff --git a/shell/hush_test/hush-read/read_t.right b/shell/hush_test/hush-read/read_t.right
index 04126cbe6..3eedae275 100644
--- a/shell/hush_test/hush-read/read_t.right
+++ b/shell/hush_test/hush-read/read_t.right
@@ -1,4 +1,4 @@
-><
-><
->test<
->test<
+>te:142<
+>:142<
+>test:0<
+>test:0<
diff --git a/shell/hush_test/hush-read/read_t.tests b/shell/hush_test/hush-read/read_t.tests
index d65f1aeaa..9fbeec517 100755
--- a/shell/hush_test/hush-read/read_t.tests
+++ b/shell/hush_test/hush-read/read_t.tests
@@ -1,10 +1,10 @@
-# bash 3.2 outputs:
+# bash 5.2 outputs:
 
-# ><
-{ echo -n 'te'; sleep 2; echo 'st'; }   | (read -t 1 reply; echo ">$reply<")
-# ><
-{               sleep 2; echo 'test'; } | (read -t 1 reply; echo ">$reply<")
-# >test<
-{ echo -n 'te'; sleep 1; echo 'st'; }   | (read -t 2 reply; echo ">$reply<")
-# >test<
-{               sleep 1; echo 'test'; } | (read -t 2 reply; echo ">$reply<")
+# >te:142<
+{ echo -n 'te'; sleep 2; echo 'st'; }   | (read -t 1 reply; echo ">$reply:$?<")
+# >:142<
+{               sleep 2; echo 'test'; } | (read -t 1 reply; echo ">$reply:$?<")
+# >test:0<
+{ echo -n 'te'; sleep 1; echo 'st'; }   | (read -t 2 reply; echo ">$reply:$?<")
+# >test:0<
+{               sleep 1; echo 'test'; } | (read -t 2 reply; echo ">$reply:$?<")
diff --git a/shell/shell_common.c b/shell/shell_common.c
index 2702ef98a..657f0df8f 100644
--- a/shell/shell_common.c
+++ b/shell/shell_common.c
@@ -55,7 +55,7 @@ const char* FAST_FUNC
 shell_builtin_read(struct builtin_read_params *params)
 {
         struct pollfd pfd[1];
-#define fd (pfd[0].fd) /* -u FD */
+#define fd (pfd->fd) /* -u FD */
         unsigned err;
         unsigned end_ms; /* -t TIMEOUT */
         int nchars; /* -n NUM */
@@ -144,7 +144,7 @@ shell_builtin_read(struct builtin_read_params *params)
                  * bash seems to ignore -p PROMPT for this use case.
                  */
                 int r;
-                pfd[0].events = POLLIN;
+                pfd->events = POLLIN;
                 r = poll(pfd, 1, /*timeout:*/ 0);
                 /* Return 0 only if poll returns 1 ("one fd ready"), else return 1: */
                 return (const char *)(uintptr_t)(r <= 0);
@@ -209,13 +209,8 @@ shell_builtin_read(struct builtin_read_params *params)
                          * 32-bit unix time wrapped (year 2038+).
                          */
                         if (timeout <= 0) { /* already late? */
-#if ENABLE_PLATFORM_MINGW32
                                 retval = (const char *)(uintptr_t)2;
                                 break;
-#else
-                                retval = (const char *)(uintptr_t)1;
-                                goto ret;
-#endif
                         }
                 }
 
@@ -224,8 +219,8 @@ shell_builtin_read(struct builtin_read_params *params)
                  * regardless of SA_RESTART-ness of that signal!
                  */
                 errno = 0;
-                pfd[0].events = POLLIN;
-//TODO race with a signal arriving just before the poll!
+                pfd->events = POLLIN;
+
 #if ENABLE_PLATFORM_MINGW32
                 /* Don't poll if timeout is -1, it hurts performance.  The
                  * caution above about interrupts isn't relevant on Windows
@@ -233,15 +228,14 @@ shell_builtin_read(struct builtin_read_params *params)
                  */
                 if (timeout >= 0)
 #endif
-                if (poll(pfd, 1, timeout) <= 0) {
-                        /* timed out, or EINTR */
+                /* test bb_got_signal, then poll(), atomically wrt signals */
+                if (check_got_signal_and_poll(pfd, timeout) <= 0) {
+                        /* timed out, or some error */
                         err = errno;
-#if ENABLE_PLATFORM_MINGW32
-                        if (!err) {
+                        if (!err) { /* timed out */
                                 retval = (const char *)(uintptr_t)2;
                                 break;
                         }
-#endif
                         retval = (const char *)(uintptr_t)1;
                         goto ret;
                 }