Modularize path to gsi and gsi-script

README.md

@@ -80,6 +80,22 @@ $ LDFLAGS=-L/usr/local/opt/openssl/lib \
   ./build.sh
 ```
 
+Gerbil expects the Gambit interpreter to be called `gsi`;
+if the Gambit interpreter has a nonstandard name or installation path
+(e.g., `gsi` is the name for the ghostscript interpreter in Arch Linux)
+then:
+1. Manually edit the file at `$GAMBIT_HOME/src/conf.sh`
+2. Continue build as normal: `cd $GERBIL_HOME/src && ./build.sh`
+
+For example, if the gambit interpreter is called `gambit-interpreter`
+instead of `gsi`, `conf.sh` should look like this:
+```
+$ export GERBIL_GSI="gambit-interpreter"
+```
+Acceptable values include:
+1. a name visible through `$PATH`
+2. an absolute path to the executable
+
 # Using Gerbil
 The Gerbil interpreter is `$GERBIL_HOME/bin/gxi`, and the compiler is
 `$GERBIL_HOME/bin/gxc`.

src/build.sh

@@ -2,14 +2,15 @@
 set -eu
 
 #===============================================================================
-# Assuming this script is run with: `cd $GERBIL_BASE/src && ./build.sh`
+# This script must be run with: `cd $GERBIL_BASE/src && ./build.sh`
 #===============================================================================
 
 ## global constants
 readonly GERBIL_SOURCE="$(pwd -P)"
 readonly GERBIL_BASE="$(dirname "${GERBIL_SOURCE}")"
 readonly GERBIL_BUILD="${GERBIL_SOURCE}/build"
 readonly GERBIL_STAGE0="${GERBIL_BASE}/bootstrap"
+readonly GERBIL_CONFIG="${GERBIL_SOURCE}/conf.sh"
 
 #===============================================================================
 ## feedback
@@ -39,18 +40,18 @@ target_setup () {
 
 compile_runtime () {
   local target_lib="${1}"
-  (cd gerbil/runtime && ./build.scm "${target_lib}")
+  (cd gerbil/runtime && "${GERBIL_GSI}" build.scm "${target_lib}")
 }
 
 finalize_build () {
   local target_lib="${1}"
   local target_bin="${2}"
   cp -v gerbil/boot/*.scm \
         gerbil/interactive/*.ss \
+        "${GERBIL_CONFIG}" \
         "${target_lib}"
   cp -v gerbil/gxi \
         gerbil/gxc \
-        gerbil/gxi-build-script \
         "${target_bin}"
   (cd "${target_bin}" && ln -s gxi gxi-script)
 }
@@ -76,7 +77,7 @@ stage0 () {
   find "${target_lib}" -name \*.scm > .build.stage0
 
   feedback_mid "compiling gerbil core"
-  gsi "${GERBIL_BUILD}/build0.scm" || die
+  "${GERBIL_GSI}" "${GERBIL_BUILD}/build0.scm" || die
 
   ## cleaning up
   rm -f .build.stage0
@@ -144,8 +145,12 @@ build_tools () {
 build_stdlib () {
   feedback_low "Building gerbil stdlib"
   export PATH="${GERBIL_BASE}/bin:${PATH}"
-  export GERBIL_HOME="${GERBIL_BASE}" #required by gxi-build-script and build.ss
-  (cd std && ./build-deps-gen.ss  && ./build.ss)
+  export GERBIL_HOME="${GERBIL_BASE}" #required by build.ss
+  (cd std \
+   && "${GERBIL_GSI}" -e '(include "~~lib/_gambit#.scm")' \
+                      "${GERBIL_BASE}/lib/gxi-init" \
+                      build-deps-gen.ss \
+   && ./build.ss)
 }
 
 build_lang () {
@@ -155,8 +160,6 @@ build_lang () {
   (cd lang && ./build.ss)
 }
 
-#===============================================================================
-## main
 build_gerbil() {
   feedback_low "Building Gerbil"
   stage0       || die
@@ -166,6 +169,11 @@ build_gerbil() {
   build_tools  || die
 }
 
+## main
+#===============================================================================
+## load configuration file
+source "${GERBIL_CONFIG}" || die
+
 ## handling command line
 if [ -z "${1+x}" ]; then
   build_gerbil

src/build/build0.scm

@@ -1,3 +1,4 @@
+@;gsi-script
 (##namespace (""))
 
 (define file-list ".build.stage0")

src/conf.sh

@@ -0,0 +1,2 @@
+# User configuration file
+export GERBIL_GSI="gsi"

src/gerbil/gxi

@@ -2,10 +2,14 @@
 set -eu
 
 if [ -z "${GERBIL_HOME:-}" ]; then
-    GERBIL_HOME=$(dirname $(cd ${0%/*} && echo $PWD))
+    GERBIL_HOME="$(dirname "$(cd ${0%/*} && echo $PWD)")"
     export GERBIL_HOME
 fi
 
+if [ -z "${GERBIL_GSI:-}" ]; then
+    source "${GERBIL_HOME}/lib/conf.sh"
+fi
+
 if [ $# -gt 0 ]; then
     case $1 in
         -:*)
@@ -25,7 +29,12 @@ if [ $# -gt 0 ]; then
 fi
 
 if [[ "x" = "x$@" ]]; then
-    gsi ${GSIOPTIONS:-} $GERBIL_HOME/lib/gxi-init $GERBIL_HOME/lib/gxi-interactive -
+    "${GERBIL_GSI}" ${GSIOPTIONS:-} \
+                    "${GERBIL_HOME}/lib/gxi-init" \
+                    "${GERBIL_HOME}/lib/gxi-interactive" \
+                    -
 else
-    gsi ${GSIOPTIONS:-} $GERBIL_HOME/lib/gxi-init "$@"
+    "${GERBIL_GSI}" ${GSIOPTIONS:-} \
+                    "${GERBIL_HOME}/lib/gxi-init" \
+                    "$@"
 fi

src/gerbil/runtime/build.scm

@@ -1,4 +1,5 @@
-#!/usr/bin/env gsi-script
+@;gsi-script
+; the above line is a directive for the gambit interpreter
 
 (##namespace (""))
 

src/std/build-deps-gen.ss

@@ -1,4 +1,3 @@
-#!/usr/bin/env gxi-build-script
 ;; -*- Gerbil -*-
 ;; build-deps depgraph generator
 (import "make" "build-config")