Re: [PATCH 1/5] pathspec: add new function to parse file

> From: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>
> 
> This will be used to support the new option '--pathspec-from-file' in
> `git add`, `git-commit`, `git reset` etc.
> 
> Note also that we specifically handle CR/LF line endings to support
> Windows better.
> 
> To simplify code, file is first parsed into `argv_array`. This allows
> to avoid refactoring `parse_pathspec()`.
> 
> I considered adding `nul_term_line` to `flags` instead, but decided
> that it doesn't fit there.
> 
> The new code is mostly taken from `cmd_update_index()` and
> `split_mail_conv()`.
> 
> Co-authored-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> Signed-off-by: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>
> ---
>   pathspec.c | 41 +++++++++++++++++++++++++++++++++++++++++
>   pathspec.h | 10 ++++++++++
>   2 files changed, 51 insertions(+)
> 
> diff --git a/pathspec.c b/pathspec.c
> index 12c2b322b3..97d4e77875 100644
> --- a/pathspec.c
> +++ b/pathspec.c
> @@ -3,6 +3,8 @@
>   #include "dir.h"
>   #include "pathspec.h"
>   #include "attr.h"
> +#include "argv-array.h"
> +#include "quote.h"
>   
>   /*
>    * Finds which of the given pathspecs match items in the index.
> @@ -613,6 +615,45 @@ void parse_pathspec(struct pathspec *pathspec,
>   	}
>   }
>   
> +void parse_pathspec_file(struct pathspec *pathspec, unsigned magic_mask,
> +			 unsigned flags, const char *prefix,
> +			 const char *file, int nul_term_line)
> +{
> +	struct argv_array parsed_file = ARGV_ARRAY_INIT;
> +	strbuf_getline_fn getline_fn = nul_term_line ? strbuf_getline_nul :
> +						       strbuf_getline;
> +	struct strbuf buf = STRBUF_INIT;
> +	struct strbuf unquoted = STRBUF_INIT;
> +	FILE *in = NULL;
> +
> +	if (!strcmp(file, "-"))
> +		in = stdin;
> +	else
> +		in = fopen(file, "r");
> +
> +	if (!in)
> +		die(_("could not open '%s' for reading"), file);

> +	while (getline_fn(&buf, in) != EOF) {
> +		if (!nul_term_line && buf.buf[0] == '"') {
> +			strbuf_reset(&unquoted);
> +			if (unquote_c_style(&unquoted, buf.buf, NULL))
> +				die(_("line is badly quoted"));

> +			strbuf_swap(&buf, &unquoted);
> +		}
> +		argv_array_push(&parsed_file, buf.buf);
> +		strbuf_reset(&buf);
> +	}
> +
> +	strbuf_release(&unquoted);
> +	strbuf_release(&buf);
> +	if (in != stdin)
> +		fclose(in);
> +
> +	parse_pathspec(pathspec, magic_mask, flags, prefix, parsed_file.argv);
> +	argv_array_clear(&parsed_file);
> +}
> +
>   void copy_pathspec(struct pathspec *dst, const struct pathspec *src)
>   {
>   	int i, j;
> diff --git a/pathspec.h b/pathspec.h
> index 1c18a2c90c..d72e0b4c4a 100644
> --- a/pathspec.h
> +++ b/pathspec.h
> @@ -85,6 +85,16 @@ void parse_pathspec(struct pathspec *pathspec,
>   		    unsigned flags,
>   		    const char *prefix,
>   		    const char **args);
> +/*
> + * Same as parse_pathspec() but uses file as input.
> + * When 'file' is exactly "-" it uses 'stdin' instead.
> + */
> +void parse_pathspec_file(struct pathspec *pathspec,
> +		    unsigned magic_mask,
> +		    unsigned flags,
> +		    const char *prefix,
> +		    const char *file,
> +		    int nul_term_line);