Merge commit '56a3b82e9692a25ef9c9269e88feac0d579ce8e8' into merge

Conflicts:
	coreutils/ls.c
	include/platform.h
	libbb/bb_basename.c

1 files changed, 32 insertions, 11 deletions

diff --git a/shell/shell_common.c b/shell/shell_common.c
index 75f4b3e54..4329ca05c 100644
--- a/shell/shell_common.c
+++ b/shell/shell_common.c
@@ -36,6 +36,10 @@ int FAST_FUNC is_well_formed_var_name(const char *s, char terminator)
 
 /* read builtin */
 
+/* Needs to be interruptible: shell mush handle traps and shell-special signals
+ * while inside read. To implement this, be sure to not loop on EINTR
+ * and return errno == EINTR reliably.
+ */
 //TODO: use more efficient setvar() which takes a pointer to malloced "VAR=VAL"
 //string. hush naturally has it, and ash has setvareq().
 //Here we can simply store "VAR=" at buffer start and store read data directly
@@ -51,6 +55,7 @@ shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val),
         const char *opt_u
 )
 {
+        unsigned err;
         unsigned end_ms; /* -t TIMEOUT */
         int fd; /* -u FD */
         int nchars; /* -n NUM */
@@ -62,6 +67,8 @@ shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val),
         int startword;
         smallint backslash;
 
+        errno = err = 0;
+
         pp = argv;
         while (*pp) {
                 if (!is_well_formed_var_name(*pp, '\0')) {
@@ -152,28 +159,40 @@ shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val),
         bufpos = 0;
         do {
                 char c;
+                struct pollfd pfd[1];
+                int timeout;
 
-                if (end_ms) {
-                        int timeout;
-                        struct pollfd pfd[1];
+                if ((bufpos & 0xff) == 0)
+                        buffer = xrealloc(buffer, bufpos + 0x100);
 
-                        pfd[0].fd = fd;
-                        pfd[0].events = POLLIN;
+                timeout = -1;
+                if (end_ms) {
                         timeout = end_ms - (unsigned)monotonic_ms();
-                        if (timeout <= 0 /* already late? */
-                         || safe_poll(pfd, 1, timeout) != 1 /* no? wait... */
-                        ) { /* timed out! */
+                        if (timeout <= 0) { /* already late? */
                                 retval = (const char *)(uintptr_t)1;
                                 goto ret;
                         }
                 }
 
-                if ((bufpos & 0xff) == 0)
-                        buffer = xrealloc(buffer, bufpos + 0x100);
-                if (nonblock_safe_read(fd, &buffer[bufpos], 1) != 1) {
+                /* We must poll even if timeout is -1:
+                 * we want to be interrupted if signal arrives,
+                 * regardless of SA_RESTART-ness of that signal!
+                 */
+                errno = 0;
+                pfd[0].fd = fd;
+                pfd[0].events = POLLIN;
+                if (poll(pfd, 1, timeout) != 1) {
+                        /* timed out, or EINTR */
+                        err = errno;
+                        retval = (const char *)(uintptr_t)1;
+                        goto ret;
+                }
+                if (read(fd, &buffer[bufpos], 1) != 1) {
+                        err = errno;
                         retval = (const char *)(uintptr_t)1;
                         break;
                 }
+
                 c = buffer[bufpos];
                 if (c == '\0' || (ENABLE_PLATFORM_MINGW32 && c == '\r'))
                         continue;
@@ -240,6 +259,8 @@ shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val),
         free(buffer);
         if (read_flags & BUILTIN_READ_SILENT)
                 tcsetattr(fd, TCSANOW, &old_tty);
+
+        errno = err;
         return retval;
 }