diff options
Diffstat (limited to 'configure')
| -rwxr-xr-x | configure | 62 |
1 files changed, 46 insertions, 16 deletions
@@ -27,29 +27,61 @@ # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # -# The #!/bin/sh might be some legacy piece of crap, -# not even up to 1990 POSIX.2 spec. So the first step -# is to look for a better shell in some known places -# and re-execute ourselves with that interpreter. +# The #!/bin/sh might be some legacy piece of junk, not even up to 1990 POSIX.2 +# spec. So the first step is to look for a better shell in some known places +# and re-execute ourselves with that interpreter, unless there is evidence we +# are already running in a usable shell. # -if test x$txr_shell = x ; then - for shell in /bin/bash /usr/bin/bash /usr/xpg4/bin/sh ; do - if test -x $shell ; then +while true ; do + # we have already recursed into a desired shell + if test "x$txr_shell" != x ; then + break + fi + + # Evidence we are running on Bash in POSIX mode. + if test x$POSIXLY_CORRECT = y ; then + break + fi + + # Evidence we are running on Bash in regular mode. + if test x$BASH_VERSION != x ; then + break + fi + + # Slow path: find a suitable shell. + # First choice is $CONFIG_SHELL, a convention from GNU Autoconf. + for shell in "$CONFIG_SHELL" \ + /bin/bash /usr/bin/bash /usr/local/bin/bash \ + /bin/dash /usr/bin/dash /usr/local/bin/dash \ + /usr/xpg4/bin/sh + do + if test -x "$shell" ; then txr_shell=$shell break fi done - if test x$txr_shell = x ; then - echo "No known POSIX shell found: falling back on /bin/sh, which may not work" - txr_shell=/bin/sh + + if test "x$txr_shell" = x ; then + echo "No known modern shell found; sticking with this one." + break; fi + + # we export txr_shell because it acts as a flag indicating the recursed case export txr_shell - exec $txr_shell $0 ${@+"$@"} -fi + echo "Re-executing using $txr_shell" + exec "$txr_shell" $0 ${@+"$@"} + break +done set -u +if [ -n "${txr_shell+y}" ] ; then + printf "Now running in %s shell\n" $txr_shell +else + printf "Running in original shell.\n" +fi + # # Save command line in a way that can be re-run. # @@ -524,8 +556,6 @@ printf "+%s+\n|%s|\n+%s+\n" $banner_box "$banner_text" $banner_box set -e -printf "We are using this shell: %s\n" $txr_shell - # # Check for GNU make # @@ -740,10 +770,10 @@ gen_config_make() # Changes to this file are lost when the above is re-run. # -# Shell used by make for running recipes; this +${txr_shell:+# Shell used by make for running recipes; this # is the as the shell we chose for the configure script, # derived from the txr_shell variable. -SHELL := $txr_shell +SHELL := $txr_shell} txr_ver := $txr_ver |