[llvm-objcopy] Add support for shell wildcards

Summary: GNU objcopy accepts the --wildcard flag to allow wildcard matching on symbol-related flags. (Note: it's implicitly true for section flags).

The basic syntax is to allow *, ?, \, and [] which work similarly to how they work in a shell. Additionally, starting a wildcard with ! causes that wildcard to prevent it from matching a flag.

Use an updated GlobPattern in libSupport to handle these patterns. It does not fully match the `fnmatch` used by GNU objcopy since named character classes (e.g. `[[:digit:]]`) are not supported, but this should support most existing use cases (mostly just `*` is what's used anyway).

Reviewers: jhenderson, MaskRay, evgeny777, espindola, alexshap

Reviewed By: MaskRay

Subscribers: nickdesaulniers, emaste, arichardson, hiraditya, jakehehrlich, abrachet, seiya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66613

llvm-svn: 375169

2 files changed, 311 insertions, 0 deletions

diff --git a/llvm/test/tools/llvm-objcopy/ELF/wildcard-flags.test b/llvm/test/tools/llvm-objcopy/ELF/wildcard-flags.test
new file mode 100644
index 00000000000..29a91cd1dc6
--- /dev/null
+++ b/llvm/test/tools/llvm-objcopy/ELF/wildcard-flags.test
@@ -0,0 +1,162 @@
+## This test checks basic functionality of glob (or "shell wildcard") matching,
+## as well as verifying all the relevant flags in llvm-objcopy and llvm-strip
+## are configured correctly.
+## For more detailed syntax tests, see wildcard-syntax.test.
+
+# RUN: yaml2obj %s > %t.o
+
+## Check that --regex and --wildcard cannot be used together.
+# RUN: not llvm-objcopy --regex --wildcard %t.o %t.err.o 2>&1 \
+# RUN:   | FileCheck %s --check-prefix=ERR
+# RUN: not llvm-strip --regex --wildcard %t.o -o %t.err.o 2>&1 \
+# RUN:   | FileCheck %s --check-prefix=ERR
+
+# ERR: error: --regex and --wildcard are incompatible
+
+## Check that section removal flags default to glob matches.
+
+## --keep-section:
+# RUN: llvm-objcopy --strip-all --keep-section='.f*' %t.o %t.ksec.1.o
+# RUN: llvm-readobj --sections %t.ksec.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,SEC,FOO-SEC
+# RUN: llvm-strip --strip-all --keep-section='.f*' %t.o -o %t.ksec.2.o
+# RUN: cmp %t.ksec.1.o %t.ksec.2.o
+
+## --only-section:
+# RUN: llvm-objcopy --strip-all --only-section='.f*' %t.o %t.osec.1.o
+# RUN: llvm-readobj --sections %t.osec.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,SEC,FOO-SEC
+
+## --remove-section:
+# RUN: llvm-objcopy --strip-debug --remove-section='.s??tab' %t.o %t.rsec.1.o
+# RUN: llvm-readobj --sections %t.rsec.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:       --check-prefixes=CHECK,SEC,FOO-SEC,BAR-SEC
+# RUN: llvm-strip --strip-debug --remove-section='.s??tab' %t.o -o %t.rsec.2.o
+# RUN: cmp %t.rsec.1.o %t.rsec.2.o
+
+## Check that symbol removal options default to literal matches. Adding -w
+## enables glob support for these options.
+
+## --globalize-symbol:
+# RUN: llvm-objcopy --globalize-symbol='*' %t.o %t.globsym.1.o
+# RUN: llvm-readobj --symbols %t.globsym.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:       --check-prefixes=CHECK,LOCAL,FOO-SYM,BAR-SYM
+
+# RUN: llvm-objcopy -w --globalize-symbol='*' %t.o %t.globsym.2.o
+# RUN: llvm-readobj --symbols %t.globsym.2.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:       --check-prefixes=CHECK,GLOBAL,FOO-SYM,BAR-SYM
+
+## --keep-symbol:
+# RUN: llvm-objcopy --discard-all --keep-symbol='f*' %t.o %t.ksym.1.o
+# RUN: llvm-readobj --symbols %t.ksym.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK
+# RUN: llvm-strip --discard-all --keep-symbol='f*' %t.o -o %t.ksym.2.o
+# RUN: cmp %t.ksym.1.o %t.ksym.2.o
+
+# RUN: llvm-objcopy --discard-all -w --keep-symbol='f*' %t.o %t.ksym.3.o
+# RUN: llvm-readobj --symbols %t.ksym.3.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,FOO-SYM
+# RUN: llvm-strip --discard-all -w --keep-symbol='f*' %t.o -o %t.ksym.4.o
+# RUN: cmp %t.ksym.3.o %t.ksym.4.o
+
+## --localize-symbol:
+## Note: Use %t.globsym.2.o instead of %t.o since those symbols are global.
+# RUN: llvm-objcopy --localize-symbol='*' %t.globsym.2.o %t.localsym.1.o
+# RUN: llvm-readobj --symbols %t.localsym.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:       --check-prefixes=CHECK,GLOBAL,FOO-SYM,BAR-SYM
+
+# RUN: llvm-objcopy -w --localize-symbol='*' %t.globsym.2.o %t.localsym.2.o
+# RUN: llvm-readobj --symbols %t.localsym.2.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:       --check-prefixes=CHECK,LOCAL,FOO-SYM,BAR-SYM
+
+## --strip-symbol:
+# RUN: llvm-objcopy --strip-symbol='f*' %t.o %t.stripsym.1.o
+# RUN: llvm-readobj --symbols %t.stripsym.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,FOO-SYM,BAR-SYM
+# RUN: llvm-strip --strip-symbol='f*' %t.o -o %t.stripsym.2.o
+# RUN: cmp %t.stripsym.1.o %t.stripsym.2.o
+
+# RUN: llvm-objcopy -w --strip-symbol='f*' %t.o %t.stripsym.3.o
+# RUN: llvm-readobj --symbols %t.stripsym.3.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,BAR-SYM
+# RUN: llvm-strip -w --strip-symbol='f*' %t.o -o %t.stripsym.4.o
+# RUN: cmp %t.stripsym.3.o %t.stripsym.4.o
+
+## --strip-unneeded-symbol:
+# RUN: llvm-objcopy --strip-unneeded-symbol='f*' %t.o %t.stripunsym.1.o
+# RUN: llvm-readobj --symbols %t.stripunsym.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,FOO-SYM,BAR-SYM
+
+# RUN: llvm-objcopy -w --strip-unneeded-symbol='f*' %t.o %t.stripunsym.2.o
+# RUN: llvm-readobj --symbols %t.stripunsym.2.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,BAR-SYM
+
+## --weaken-symbol:
+## Note: Use %t.globsym.2.o instead of %t.o since those symbols are global.
+# RUN: llvm-objcopy --weaken-symbol='*' %t.globsym.2.o %t.weaksym.1.o
+# RUN: llvm-readobj --symbols %t.weaksym.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:       --check-prefixes=CHECK,GLOBAL,FOO-SYM,BAR-SYM
+
+# RUN: llvm-objcopy -w --weaken-symbol='*' %t.globsym.2.o %t.weaksym.2.o
+# RUN: llvm-readobj --symbols %t.weaksym.2.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:       --check-prefixes=CHECK,WEAK,FOO-SYM,BAR-SYM
+
+## --keep-global-symbol:
+## Note: Use %t.globsym.2.o instead of %t.o since those symbols are global.
+# RUN: llvm-objcopy --keep-global-symbol='*' %t.globsym.2.o %t.keepgsym.1.o
+# RUN: llvm-readobj --symbols %t.keepgsym.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:       --check-prefixes=CHECK,LOCAL,FOO-SYM,BAR-SYM
+
+# RUN: llvm-objcopy -w --keep-global-symbol='*' %t.globsym.2.o %t.keepgsym.2.o
+# RUN: llvm-readobj --symbols %t.keepgsym.2.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:       --check-prefixes=CHECK,GLOBAL,FOO-SYM,BAR-SYM
+
+## Check that -w is accepted as an alias for --wildcard.
+# RUN: llvm-objcopy --wildcard --keep-global-symbol='*' %t.globsym.2.o %t.keepgsym.3.o
+# RUN: cmp %t.keepgsym.2.o %t.keepgsym.3.o
+
+# CHECK:   LoadName:
+# CHECK:   Name: (0)
+
+# FOO-SEC: Name: .foo
+
+# FOO-SYM: Name: foo
+# GLOBAL:  Binding: Global
+# WEAK:    Binding: Weak
+# LOCAL:   Binding: Local
+
+# BAR-SEC: Name: .bar
+# BAR-SYM: Name: bar
+# GLOBAL:  Binding: Global
+# WEAK:    Binding: Weak
+# LOCAL:   Binding: Local
+
+# SEC:     Name: .shstrtab
+
+!ELF
+FileHeader:
+  Class:     ELFCLASS64
+  Data:      ELFDATA2LSB
+  Type:      ET_REL
+  Machine:   EM_X86_64
+Sections:
+  - Name:    .foo
+    Type:    SHT_PROGBITS
+  - Name:    .bar
+    Type:    SHT_PROGBITS
+Symbols:
+  - Name:    foo
+    Type:    STT_FUNC
+    Section: .foo
+  - Name:    bar
+    Type:    STT_FUNC
+    Section: .foo
diff --git a/llvm/test/tools/llvm-objcopy/ELF/wildcard-syntax.test b/llvm/test/tools/llvm-objcopy/ELF/wildcard-syntax.test
new file mode 100644
index 00000000000..05642896727
--- /dev/null
+++ b/llvm/test/tools/llvm-objcopy/ELF/wildcard-syntax.test
@@ -0,0 +1,149 @@
+## This test checks that llvm-objcopy accepts glob (or "shell wildcard") syntax
+## for the --wildcard (-w) flag correctly.
+
+# RUN: yaml2obj --docnum=1 %s > %t.o
+
+## * matches all characters.
+# RUN: llvm-objcopy --remove-section='.f*' %t.o %t.glob.o
+# RUN: llvm-readobj --sections %t.glob.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,BAR
+
+## Glob matches are full matches. ("*a" does not match ".bar").
+# RUN: llvm-objcopy --remove-section='*a' %t.o %t.full.o
+# RUN: llvm-readobj --sections %t.full.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,FOO,BAR
+
+## ? matches one character.
+# RUN: llvm-objcopy --remove-section='.b?r' %t.o %t.question.o
+# RUN: llvm-readobj --sections %t.question.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,FOO
+
+## ! (as a leading character) prevents matches, and is not dependent on
+## ordering.
+# RUN: llvm-objcopy --remove-section='.???' --remove-section='!.f*' \
+# RUN:   %t.o %t.negmatch1.o
+# RUN: llvm-readobj --sections %t.negmatch1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,FOO
+# RUN: llvm-objcopy --remove-section='!.f*' --remove-section='.???' \
+# RUN:   %t.o %t.negmatch2.o
+# RUN: llvm-readobj --sections %t.negmatch2.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,FOO
+# RUN: llvm-objcopy --remove-section='.???' --remove-section='!.f*' \
+# RUN:   --remove-section='.???' %t.o %t.negmatch3.o
+# RUN: llvm-readobj --sections %t.negmatch3.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,FOO
+
+## [a-z] matches a range of characters.
+# RUN: llvm-objcopy --remove-section='.[a-c][a-a][q-s]' %t.o %t.range.o
+# RUN: llvm-readobj --sections %t.range.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,FOO
+
+## [^a-z] or [!a-z] match a negated range of characters.
+# RUN: llvm-objcopy --remove-section='.[^x]oo' %t.o %t.negrange.1.o
+# RUN: llvm-readobj --sections %t.negrange.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,BAR
+# RUN: llvm-objcopy --remove-section='.[!x]oo' %t.o %t.negrange.2.o
+# RUN: llvm-readobj --sections %t.negrange.2.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: --check-prefixes=CHECK,BAR
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_REL
+  Machine: EM_X86_64
+Sections:
+  - Name: .foo
+    Type: SHT_PROGBITS
+  - Name: .bar
+    Type: SHT_PROGBITS
+
+## Use a separate test file with special characters for the following tests.
+
+# RUN: yaml2obj --docnum=2 %s > %t.special.o
+
+## \ escapes wildcard characters.
+# RUN: llvm-objcopy --remove-section='\*' %t.special.o %t.escape.1.o
+# RUN: llvm-readobj --sections %t.escape.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:   --check-prefixes=CHECK,DOT,QUESTION,LEFT-BRACKET,RIGHT-BRACKET,INVALID-GLOB,Z,XYZ,FOO
+# RUN: llvm-objcopy --remove-section='\?' %t.special.o %t.escape.2.o
+# RUN: llvm-readobj --sections %t.escape.2.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:   --check-prefixes=CHECK,DOT,ASTERISK,LEFT-BRACKET,RIGHT-BRACKET,INVALID-GLOB,Z,XYZ,FOO
+
+## Special characters are not treated like regular expression characters.
+# RUN: llvm-objcopy --remove-section='.' %t.special.o %t.dot.o
+# RUN: llvm-readobj --sections %t.dot.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:   --check-prefixes=CHECK,ASTERISK,QUESTION,LEFT-BRACKET,RIGHT-BRACKET,INVALID-GLOB,Z,XYZ,FOO
+
+## Special characters in character classes are treated literally.
+## [*] should not get expanded to [.*], which would match both '.' and '*'
+# RUN: llvm-objcopy --remove-section='[*]' %t.special.o %t.class.1.o
+# RUN: llvm-readobj --sections %t.class.1.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:   --check-prefixes=CHECK,DOT,QUESTION,LEFT-BRACKET,RIGHT-BRACKET,INVALID-GLOB,Z,XYZ,FOO
+
+## ] doesn't close the character class as a first character. This glob matches
+## a single character which is one of ']xyz'. ']' and 'z' are removed, and more explicitly,
+## section 'xyz]' is not removed, i.e. the glob is not interpreted as "an empty
+## character class followed by 'xyz]'"
+# RUN: llvm-objcopy --remove-section='[]xyz]' %t.special.o %t.class.2.o
+# RUN: llvm-readobj --sections %t.class.2.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:   --check-prefixes=CHECK,DOT,ASTERISK,QUESTION,LEFT-BRACKET,INVALID-GLOB,XYZ,FOO
+
+## An invalid glob expression is interpreted as a literal instead.
+# RUN: llvm-objcopy --remove-section='][]' %t.special.o %t.class.3.o 2>&1 \
+# RUN:   | FileCheck %s --check-prefix=WARN
+# RUN: llvm-readobj --sections %t.class.3.o \
+# RUN:   | FileCheck %s --implicit-check-not=Name: \
+# RUN:   --check-prefixes=CHECK,DOT,ASTERISK,QUESTION,LEFT-BRACKET,RIGHT-BRACKET,Z,XYZ,FOO
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_REL
+  Machine: EM_X86_64
+Sections:
+  - Name: .
+    Type: SHT_PROGBITS
+  - Name: '*'
+    Type: SHT_PROGBITS
+  - Name: '?'
+    Type: SHT_PROGBITS
+  - Name: '['
+    Type: SHT_PROGBITS
+  - Name: ']'
+    Type: SHT_PROGBITS
+  - Name: '][]'
+    Type: SHT_PROGBITS
+  - Name: z
+    Type: SHT_PROGBITS
+  - Name: 'xyz]'
+    Type: SHT_PROGBITS
+  - Name: '[]xyz]'
+    Type: SHT_PROGBITS
+  - Name: .foo
+    Type: SHT_PROGBITS
+
+# WARN: warning: invalid glob pattern: ][]
+
+# CHECK: LoadName:
+# CHECK:         Name: (0)
+# DOT:           Name: .
+# ASTERISK:      Name: *
+# QUESTION:      Name: ?
+# LEFT-BRACKET:  Name: [
+# RIGHT-BRACKET: Name: ]
+# INVALID-GLOB:  Name: ][]
+# Z:             Name: z
+# XYZ:           Name: xyz]
+# XYZ:           Name: []xyz]
+# FOO:           Name: .foo
+# BAR:           Name: .bar
+# CHECK:         Name: .symtab
+# CHECK:         Name: .strtab
+# CHECK:         Name: .shstrtab