diff options
Diffstat (limited to 'shell/shell_common.c')
| -rw-r--r-- | shell/shell_common.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/shell/shell_common.c b/shell/shell_common.c index 86a6493..a5c455c 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')) { @@ -153,6 +160,8 @@ shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val), do { char c; + errno = 0; + if (end_ms) { int timeout; struct pollfd pfd[1]; @@ -161,8 +170,9 @@ shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val), pfd[0].events = POLLIN; timeout = end_ms - (unsigned)monotonic_ms(); if (timeout <= 0 /* already late? */ - || safe_poll(pfd, 1, timeout) != 1 /* no? wait... */ + || poll(pfd, 1, timeout) != 1 /* no? wait... */ ) { /* timed out! */ + err = errno; retval = (const char *)(uintptr_t)1; goto ret; } @@ -170,7 +180,8 @@ shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val), if ((bufpos & 0xff) == 0) buffer = xrealloc(buffer, bufpos + 0x100); - if (nonblock_immune_read(fd, &buffer[bufpos], 1) != 1) { + if (nonblock_immune_read(fd, &buffer[bufpos], 1, /*loop_on_EINTR:*/ 0) != 1) { + err = errno; retval = (const char *)(uintptr_t)1; break; } @@ -240,6 +251,8 @@ 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; } |