var(win32): do report the GIT_SHELL_PATH that is actually used

Changes since v2:

* Now fspathncmp() is overridden on Windows just like fspathcmp().
* The win32_fspath*cmp() functions now respect core.ignoreCase.

Changes since v1:

* This patch series now shares the logic that determines the path of the Unix shell that Git uses between prepare_shell_cmd() and git var GIT_SHELL_PATH.

Johannes Schindelin (7):
run-command: refactor getting the Unix shell path into its own
function
strvec: declare the strvec_push_nodup() function globally
win32: override fspathcmp() with a directory separator-aware version mingw(is_msys2_sh): handle forward slashes in the sh.exe path, too run-command(win32): resolve the path to the Unix shell early
run-command: declare the git_shell_path() function globally var(win32): do report the GIT_SHELL_PATH that is actually used

 builtin/var.c             |  3 ++-
 compat/mingw.c            |  2 +-
 compat/win32/path-utils.c | 37 +++++++++++++++++++++++++++++++++++++
 compat/win32/path-utils.h |  4 ++++
 dir.c                     |  4 ++--
 dir.h                     |  4 ++--
 git-compat-util.h         |  8 ++++++++
 run-command.c             | 17 ++++++++++++-----
 run-command.h             |  5 +++++
 strvec.c                  |  2 +-
 strvec.h                  |  3 +++
 t/t0007-git-var.sh        |  2 +-
 12 files changed, 78 insertions(+), 13 deletions(-)

base-commit: 06e570c0dfb2a2deb64d217db78e2ec21672f558
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1760%2Fdscho%2Fgit-var-on-windows-v3
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1760/dscho/git-var-on-windows-v3
Pull-Request: https://github.com/gitgitgadget/git/pull/1760

Range-diff vs v2:

 1:  e0970381042 = 1:  e0970381042 run-command: refactor getting the Unix shell path into its own function
 2:  91ebccbc39f = 2:  91ebccbc39f strvec: declare the `strvec_push_nodup()` function globally
 3:  a718183bb3b ! 3:  f46315ac0b2 win32: override `fspathcmp()` with a directory separator-aware version
     @@ Commit message
          This means that the paths `a/b` and `a\b` are equivalent, and
          `fspathcmp()` needs to be made aware of that fact.
      
     +    Note that we have to override both `fspathcmp()` and `fspathncmp()`, and
     +    the former cannot be a mere pre-processor constant that transforms calls
     +    to `fspathcmp(a, b)` into `fspathncmp(a, b, (size_t)-1)` because the
     +    function `report_collided_checkout()` in `unpack-trees.c` wants to
     +    assign `list.cmp = fspathcmp`.
     +
     +    Also note that `fspatheq()` does _not_ need to be overridden because it
     +    calls `fspathcmp()` internally.
     +
          Signed-off-by: Johannes Schindelin <[email protected]>
      
       ## compat/win32/path-utils.c ##
     +@@
     + #include "../../git-compat-util.h"
     ++#include "../../environment.h"
     + 
     + int win32_has_dos_drive_prefix(const char *path)
     + {
      @@ compat/win32/path-utils.c: int win32_offset_1st_component(const char *path)
       
       	return pos + is_dir_sep(*pos) - path;
       }
      +
     -+int win32_fspathcmp(const char *a, const char *b)
     ++int win32_fspathncmp(const char *a, const char *b, size_t count)
      +{
      +	int diff;
      +
      +	for (;;) {
     ++		if (!count--)
     ++			return 0;
      +		if (!*a)
     -+			return !*b ? 0 : -1;
     ++			return *b ? -1 : 0;
      +		if (!*b)
      +			return +1;
      +
     @@ compat/win32/path-utils.c: int win32_offset_1st_component(const char *path)
      +		} else if (is_dir_sep(*b))
      +			return +1;
      +
     -+		diff = (unsigned char)tolower(*(a++)) - (unsigned char)tolower(*(b++));
     ++		diff = ignore_case ?
     ++			(unsigned char)tolower(*a) - (int)(unsigned char)tolower(*b) :
     ++			(unsigned char)*a - (int)(unsigned char)*b;
      +		if (diff)
      +			return diff;
     ++		a++;
     ++		b++;
      +	}
     ++}
     ++
     ++int win32_fspathcmp(const char *a, const char *b)
     ++{
     ++	return win32_fspathncmp(a, b, (size_t)-1);
      +}
      
       ## compat/win32/path-utils.h ##
     @@ compat/win32/path-utils.h: static inline int win32_has_dir_sep(const char *path)
       #define offset_1st_component win32_offset_1st_component
      +int win32_fspathcmp(const char *a, const char *b);
      +#define fspathcmp win32_fspathcmp
     ++int win32_fspathncmp(const char *a, const char *b, size_t count);
     ++#define fspathncmp win32_fspathncmp
       
       #endif
      
     @@ dir.c: int count_slashes(const char *s)
       {
       	return ignore_case ? strcasecmp(a, b) : strcmp(a, b);
       }
     +@@ dir.c: int fspatheq(const char *a, const char *b)
     + 	return !fspathcmp(a, b);
     + }
     + 
     +-int fspathncmp(const char *a, const char *b, size_t count)
     ++int git_fspathncmp(const char *a, const char *b, size_t count)
     + {
     + 	return ignore_case ? strncasecmp(a, b, count) : strncmp(a, b, count);
     + }
      
       ## dir.h ##
      @@ dir.h: int remove_dir_recursively(struct strbuf *path, int flag);
     @@ dir.h: int remove_dir_recursively(struct strbuf *path, int flag);
      -int fspathcmp(const char *a, const char *b);
      +int git_fspathcmp(const char *a, const char *b);
       int fspatheq(const char *a, const char *b);
     - int fspathncmp(const char *a, const char *b, size_t count);
     +-int fspathncmp(const char *a, const char *b, size_t count);
     ++int git_fspathncmp(const char *a, const char *b, size_t count);
       unsigned int fspathhash(const char *str);
     + 
     + /*
      
       ## git-compat-util.h ##
      @@ git-compat-util.h: static inline int git_offset_1st_component(const char *path)
       #define offset_1st_component git_offset_1st_component
       #endif
       
     -+
      +#ifndef fspathcmp
      +#define fspathcmp git_fspathcmp
      +#endif
     ++
     ++#ifndef fspathncmp
     ++#define fspathncmp git_fspathncmp
     ++#endif
      +
       #ifndef is_valid_path
       #define is_valid_path(path) 1
 4:  f04cfd91bd9 = 4:  60fde81d35c mingw(is_msys2_sh): handle forward slashes in the `sh.exe` path, too
 5:  707daf246bd = 5:  797cf9094ea run-command(win32): resolve the path to the Unix shell early
 6:  a74a7b4bb11 = 6:  7c53a4f4707 run-command: declare the `git_shell_path()` function globally
 7:  8bfd23cfa00 = 7:  7c8eba5bfd8 var(win32): do report the GIT_SHELL_PATH that is actually used

gitgitgadget