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Diffstat (limited to 'sysdeps/s390/s390-32/dl-machine.h')
-rw-r--r--sysdeps/s390/s390-32/dl-machine.h45
1 files changed, 38 insertions, 7 deletions
diff --git a/sysdeps/s390/s390-32/dl-machine.h b/sysdeps/s390/s390-32/dl-machine.h
index c56185c..0fd5a4f 100644
--- a/sysdeps/s390/s390-32/dl-machine.h
+++ b/sysdeps/s390/s390-32/dl-machine.h
@@ -166,18 +166,49 @@ _dl_start_user:\n\
# See if we were run as a command with the executable file\n\
# name as an extra leading argument.\n\
l %r1,_dl_skip_args@GOT12(0,%r12)\n\
- l %r1,0(%r1) # load _dl_skip_args\n\
+ l %r1,0(%r1) # load _dl_skip_args\n\
+ ltr %r1,%r1\n\
+ je .L4 # Skip the arg adjustment if there were none.\n\
# Get the original argument count.\n\
l %r0,96(%r15)\n\
# Subtract _dl_skip_args from it.\n\
sr %r0,%r1\n\
- # Adjust the stack pointer to skip _dl_skip_args words.\n\
- sll %r1,2\n\
- ar %r15,%r1\n\
- # Set the back chain to zero again\n\
- xc 0(4,%r15),0(%r15)\n\
# Store back the modified argument count.\n\
st %r0,96(%r15)\n\
+ # Copy argv and envp forward to account for skipped argv entries.\n\
+ # We skipped at least one argument or we would not get here.\n\
+ la %r6,100(%r15) # Destination pointer i.e. &argv[0]\n\
+ lr %r5,%r6\n\
+ lr %r0,%r1\n\
+ sll %r0,2\n # Number of skipped bytes.\n\
+ ar %r5,%r0 # Source pointer = Dest + Skipped args.\n\
+ # argv copy loop:\n\
+.L1: l %r7,0(%r5) # Load a word from the source.\n\
+ st %r7,0(%r6) # Store the word in the destination.\n\
+ ahi %r5,4\n\
+ ahi %r6,4\n\
+ ltr %r7,%r7\n\
+ jne .L1 # Stop after copying the NULL.\n\
+ # envp copy loop:\n\
+.L2: l %r7,0(%r5) # Load a word from the source.\n\
+ st %r7,0(%r6) # Store the word in the destination.\n\
+ ahi %r5,4\n\
+ ahi %r6,4\n\
+ ltr %r7,%r7\n\
+ jne .L2 # Stop after copying the NULL.\n\
+ # Now we have to zero out the envp entries after NULL to allow\n\
+ # start.S to properly find auxv by skipping zeroes.\n\
+ # zero out loop:\n\
+ lhi %r7,0\n\
+.L3: st %r7,0(%r6) # Store zero.\n\
+ ahi %r6,4 # Advance dest pointer.\n\
+ ahi %r1,-1 # Subtract one from the word count.\n\
+ ltr %r1,%r1\n\
+ jne .L3 # Keep copying if the word count is non-zero.\n\
+ # Adjust _dl_argv\n\
+ la %r6,100(%r15)\n\
+ l %r1,_dl_argv@GOT(%r12)\n\
+ st %r6,0(%r1)\n\
# The special initializer gets called with the stack just\n\
# as the application's entry point will see it; it can\n\
# switch stacks if it moves these contents over.\n\
@@ -185,7 +216,7 @@ _dl_start_user:\n\
# Call the function to run the initializers.\n\
# Load the parameters:\n\
# (%r2, %r3, %r4, %r5) = (_dl_loaded, argc, argv, envp)\n\
- l %r2,_rtld_local@GOT(%r12)\n\
+.L4: l %r2,_rtld_local@GOT(%r12)\n\
l %r2,0(%r2)\n\
l %r3,96(%r15)\n\
la %r4,100(%r15)\n\