Fix bash scripts

Author: var77

scripts/check_symbols.sh

@@ -6,7 +6,7 @@ SCRIPT=$(realpath "$0")
 THIS_DIR=$(dirname "$SCRIPT")
 
 # get all the symbols our shared library assumes are externally provided
-MAYBE_EXTERN=$(nm -u $1 | awk '{print $2}' | sed  -e 's/@/@@/' | sed -n -e 's/@@.*$//p')
+MAYBE_EXTERN=$(nm -D $1 | grep ' U ' | awk '{print $2}' | sed -e 's/@.*//')
 
 # get all the symbols that are externally provided
 EXTERN_PROVIDED=$($THIS_DIR/extern_defined.sh)

scripts/extern_defined.sh

@@ -35,20 +35,26 @@ IFS=$'\n\t'
 
 PG_BIN=$(pg_config --bindir)/postgres
 
-nm -D  $PG_BIN | grep " T " | awk '{print $3}' | sed -n -e 's/@.*$//p'
+# " T " - text symbol
+nm -D  $PG_BIN | grep " T " | awk '{print $3}' | sed -e 's/@.*$//p'
 # global bss symbol in postgres
-nm -D  $PG_BIN | grep " B " | awk '{print $3}' | sed -n -e 's/@.*$//p'
+nm -D  $PG_BIN | grep " B " | awk '{print $3}' | sed -e 's/@.*$//p'
 # postgres weak symbols
-nm -D  $PG_BIN | grep " w " | awk '{print $2}' | sed -n -e 's/@.*$//p'
+nm -D  $PG_BIN | grep " w " | awk '{print $2}' | sed -e 's/@.*$//p'
 
 # Get a list of shared library dependencies using ldd
 dependencies=$(ldd "$PG_BIN" | awk '{print $3}' | grep -v "not a dynamic executable")
 
 # Loop through the dependencies and extract symbols
 for dependency in $dependencies; do
-   nm -D "$dependency" | awk '/ U / {print $3}' | sed -n -e 's/@.*$//p'
-   nm -D "$dependency" | awk '/ i / {print $3}' | sed -n -e 's/@.*$//p'
-   nm -D "$dependency" | awk '/ T / {print $3}' | sed -n -e 's/@.*$//p'
-   nm -D "$dependency" | awk '/ V / {print $3}' | sed -n -e 's/@.*$//p'
-   nm -D "$dependency" | awk '/ W / {print $3}' | sed -n -e 's/@.*$//p'
+   # " U " - undefined symbol
+   nm -D "$dependency" | awk '/ U / {print $3}' | sed -e 's/@.*$//p'
+   # " i " - the symbol is an indirect reference to another symbol. This is often used for compiler-generated code
+   nm -D "$dependency" | awk '/ i / {print $3}' | sed -e 's/@.*$//p'
+   # " T " - The symbol is a text (code) symbol, representing a function or code that can be executed
+   nm -D "$dependency" | awk '/ T / {print $3}' | sed -e 's/@.*$//p'
+   # " V " - the symbol is a weak object
+   nm -D "$dependency" | awk '/ V / {print $3}' | sed -e 's/@.*$//p'
+   # " W " - the symbol is a weak symbol that has not been specifically tagged as weak object symbol
+   nm -D "$dependency" | awk '/ W / {print $3}' | sed -e 's/@.*$//p'
 done