Re: [PATCH 2/3] archive: specfile support (--pretty=format: in archive files)

@@ -432,7 +432,10 @@ several placeholders when adding this file to an archive.  The
 expansion depends on the availability of a commit ID, i.e. if
 gitlink:git-archive[1] has been given a tree instead of a commit or a
 tag then no replacement will be done.  The placeholders are the same
-as those for the option `--pretty=format:` of gitlink:git-log[1].
+as those for the option `--pretty=format:` of gitlink:git-log[1],
+except that they need to be wrapped like this: `$Format:PLACEHOLDERS$`
+in the file.  E.g. the string `$Format:%H$` will be replaced by the
+commit hash.
 
 
 GIT

@@ -81,14 +81,58 @@ static int run_remote_archiver(const char *remote, int argc,
 	return !!rv;
 }
 
+static void *format_specfile(const struct commit *commit, const char *format,
+                             unsigned long *sizep)
+{
+	unsigned long len = *sizep, result_len = 0;
+	const char *a = format;
+	char *result = NULL;
+
+	for (;;) {
+		const char *b, *c;
+		char *fmt, *formatted = NULL;
+		unsigned long a_len, fmt_len, formatted_len, allocated = 0;
+
+		b = memchr(a, '$', len);
+		if (!b || a + len < b + 9 || memcmp(b + 1, "Format:", 7))
+			break;
+		c = memchr(b + 8, '$', len - 8);
+		if (!c)
+			break;
+
+		a_len = b - a;
+		fmt_len = c - b - 8;
+		fmt = xmalloc(fmt_len + 1);
+		memcpy(fmt, b + 8, fmt_len);
+		fmt[fmt_len] = '\0';
+
+		formatted_len = format_commit_message(commit, fmt, &formatted,
+		                                      &allocated);
+		result = xrealloc(result, result_len + a_len + formatted_len);
+		memcpy(result + result_len, a, a_len);
+		memcpy(result + result_len + a_len, formatted, formatted_len);
+		result_len += a_len + formatted_len;
+		len -= c + 1 - a;
+		a = c + 1;
+	}
+
+	if (result && len) {
+		result = xrealloc(result, result_len + len);
+		memcpy(result + result_len, a, len);
+		result_len += len;
+	}
+
+	*sizep = result_len;
+
+	return result;
+}
+
 static void *convert_to_archive(const char *path,
                                 const void *src, unsigned long *sizep,
                                 const struct commit *commit)
 {
 	static struct git_attr *attr_specfile;
 	struct git_attr_check check[1];
-	char *interpolated = NULL;
-	unsigned long allocated = 0;
 
 	if (!commit)
 		return NULL;

@@ -102,9 +146,7 @@ static void *convert_to_archive(const char *path,
 	if (!ATTR_TRUE(check[0].value))
 		return NULL;
 
-	*sizep = format_commit_message(commit, src, &interpolated, &allocated);
-
-	return interpolated;
+	return format_specfile(commit, src, sizep);
 }
 
 void *sha1_file_to_archive(const char *path, const unsigned char *sha1,

@@ -36,7 +36,7 @@ test_expect_success \
      echo simple textfile >a/a &&
      mkdir a/bin &&
      cp /bin/sh a/bin &&
-     printf "%s" "$SPECFILEFORMAT" >a/specfile &&
+     printf "A\$Format:%s\$O" "$SPECFILEFORMAT" >a/specfile &&
      ln -s a a/l1 &&
      (p=long_path_to_a_file && cd a &&
       for depth in 1 2 3 4 5; do mkdir $p && cd $p; done &&

@@ -119,7 +119,7 @@ test_expect_success \
 
 test_expect_success \
      'validate specfile contents' \
-     'git log --max-count=1 "--pretty=format:$SPECFILEFORMAT" HEAD \
+     'git log --max-count=1 "--pretty=format:A${SPECFILEFORMAT}O" HEAD \
       >f/a/specfile.expected &&
       diff f/a/specfile.expected f/a/specfile'
 

@@ -424,10 +424,10 @@ frotz	unspecified
 Creating an archive
 ~~~~~~~~~~~~~~~~~~~
 
-`specfile`
-^^^^^^^^^^
+`export-subst`
+^^^^^^^^^^^^^^
 
-If the attribute `specfile` is set for a file then git will expand
+If the attribute `export-subst` is set for a file then git will expand
 several placeholders when adding this file to an archive.  The
 expansion depends on the availability of a commit ID, i.e. if
 gitlink:git-archive[1] has been given a tree instead of a commit or a

@@ -81,8 +81,8 @@ static int run_remote_archiver(const char *remote, int argc,
 	return !!rv;
 }
 
-static void *format_specfile(const struct commit *commit, const char *format,
-                             unsigned long *sizep)
+static void *format_subst(const struct commit *commit, const char *format,
+                          unsigned long *sizep)
 {
 	unsigned long len = *sizep, result_len = 0;
 	const char *a = format;

@@ -131,22 +131,22 @@ static void *convert_to_archive(const char *path,
                                 const void *src, unsigned long *sizep,
                                 const struct commit *commit)
 {
-	static struct git_attr *attr_specfile;
+	static struct git_attr *attr_export_subst;
 	struct git_attr_check check[1];
 
 	if (!commit)
 		return NULL;
 
-        if (!attr_specfile)
-                attr_specfile = git_attr("specfile", 8);
+        if (!attr_export_subst)
+                attr_export_subst = git_attr("export-subst", 12);
 
-	check[0].attr = attr_specfile;
+	check[0].attr = attr_export_subst;
 	if (git_checkattr(path, ARRAY_SIZE(check), check))
 		return NULL;
 	if (!ATTR_TRUE(check[0].value))
 		return NULL;
 
-	return format_specfile(commit, src, sizep);
+	return format_subst(commit, src, sizep);
 }
 
 void *sha1_file_to_archive(const char *path, const unsigned char *sha1,

@@ -28,7 +28,7 @@ commit id embedding:
 TAR=${TAR:-tar}
 UNZIP=${UNZIP:-unzip}
 
-SPECFILEFORMAT=%H%n
+SUBSTFORMAT=%H%n
 
 test_expect_success \
     'populate workdir' \

@@ -36,7 +36,7 @@ test_expect_success \
      echo simple textfile >a/a &&
      mkdir a/bin &&
      cp /bin/sh a/bin &&
-     printf "A\$Format:%s\$O" "$SPECFILEFORMAT" >a/specfile &&
+     printf "A\$Format:%s\$O" "$SUBSTFORMAT" >a/substfile &&
      ln -s a a/l1 &&
      (p=long_path_to_a_file && cd a &&
       for depth in 1 2 3 4 5; do mkdir $p && cd $p; done &&

@@ -108,20 +108,20 @@ test_expect_success \
     'diff -r a c/prefix/a'
 
 test_expect_success \
-    'create an archive with a specfile' \
-    'echo specfile specfile >a/.gitattributes &&
+    'create an archive with a substfile' \
+    'echo substfile export-subst >a/.gitattributes &&
      git archive HEAD >f.tar &&
      rm a/.gitattributes'
 
 test_expect_success \
-    'extract specfile' \
+    'extract substfile' \
     '(mkdir f && cd f && $TAR xf -) <f.tar'
 
 test_expect_success \
-     'validate specfile contents' \
-     'git log --max-count=1 "--pretty=format:A${SPECFILEFORMAT}O" HEAD \
-      >f/a/specfile.expected &&
-      diff f/a/specfile.expected f/a/specfile'
+     'validate substfile contents' \
+     'git log --max-count=1 "--pretty=format:A${SUBSTFORMAT}O" HEAD \
+      >f/a/substfile.expected &&
+      diff f/a/substfile.expected f/a/substfile'
 
 test_expect_success \
     'git archive --format=zip' \

@@ -28,6 +28,8 @@ all::
 #
 # Define NO_STRCASESTR if you don't have strcasestr.
 #
+# Define NO_MEMMEM if you don't have memmem.
+#
 # Define NO_STRLCPY if you don't have strlcpy.
 #
 # Define NO_STRTOUMAX if you don't have strtoumax in the C library.

@@ -402,6 +404,7 @@ ifeq ($(uname_S),SunOS)
 	NEEDS_NSL = YesPlease
 	SHELL_PATH = /bin/bash
 	NO_STRCASESTR = YesPlease
+	NO_MEMMEM = YesPlease
 	NO_HSTRERROR = YesPlease
 	ifeq ($(uname_R),5.8)
 		NEEDS_LIBICONV = YesPlease

@@ -424,6 +427,7 @@ ifeq ($(uname_O),Cygwin)
 	NO_D_TYPE_IN_DIRENT = YesPlease
 	NO_D_INO_IN_DIRENT = YesPlease
 	NO_STRCASESTR = YesPlease
+	NO_MEMMEM = YesPlease
 	NO_SYMLINK_HEAD = YesPlease
 	NEEDS_LIBICONV = YesPlease
 	NO_FAST_WORKING_DIRECTORY = UnfortunatelyYes

@@ -442,6 +446,7 @@ ifeq ($(uname_S),FreeBSD)
 endif
 ifeq ($(uname_S),OpenBSD)
 	NO_STRCASESTR = YesPlease
+	NO_MEMMEM = YesPlease
 	NEEDS_LIBICONV = YesPlease
 	BASIC_CFLAGS += -I/usr/local/include
 	BASIC_LDFLAGS += -L/usr/local/lib

@@ -456,6 +461,7 @@ ifeq ($(uname_S),NetBSD)
 endif
 ifeq ($(uname_S),AIX)
 	NO_STRCASESTR=YesPlease
+	NO_MEMMEM = YesPlease
 	NO_STRLCPY = YesPlease
 	NEEDS_LIBICONV=YesPlease
 endif

@@ -467,6 +473,7 @@ ifeq ($(uname_S),IRIX64)
 	NO_IPV6=YesPlease
 	NO_SETENV=YesPlease
 	NO_STRCASESTR=YesPlease
+	NO_MEMMEM = YesPlease
 	NO_STRLCPY = YesPlease
 	NO_SOCKADDR_STORAGE=YesPlease
 	SHELL_PATH=/usr/gnu/bin/bash

@@ -661,6 +668,10 @@ ifdef NO_HSTRERROR
 	COMPAT_CFLAGS += -DNO_HSTRERROR
 	COMPAT_OBJS += compat/hstrerror.o
 endif
+ifdef NO_MEMMEM
+	COMPAT_CFLAGS += -DNO_MEMMEM
+	COMPAT_OBJS += compat/memmem.o
+endif
 
 ifeq ($(TCLTK_PATH),)
 NO_TCLTK=NoThanks

@@ -0,0 +1,29 @@
+#include "../git-compat-util.h"
+
+void *gitmemmem(const void *haystack, size_t haystack_len,
+                const void *needle, size_t needle_len)
+{
+	const char *begin = haystack;
+	const char *last_possible = begin + haystack_len - needle_len;
+
+	/*
+	 * The first occurrence of the empty string is deemed to occur at
+	 * the beginning of the string.
+	 */
+	if (needle_len == 0)
+		return (void *)begin;
+
+	/*
+	 * Sanity check, otherwise the loop might search through the whole
+	 * memory.
+	 */
+	if (haystack_len < needle_len)
+		return NULL;
+
+	for (; begin <= last_possible; begin++) {
+		if (!memcmp(begin, needle, needle_len))
+			return (void *)begin;
+	}
+
+	return NULL;
+}

@@ -172,6 +172,12 @@ extern uintmax_t gitstrtoumax(const char *, char **, int);
 extern const char *githstrerror(int herror);
 #endif
 
+#ifdef NO_MEMMEM
+#define memmem gitmemmem
+void *gitmemmem(const void *haystack, size_t haystacklen,
+                const void *needle, size_t needlelen);
+#endif
+
 extern void release_pack_memory(size_t, int);
 
 static inline char* xstrdup(const char *str)

@@ -432,7 +432,10 @@ several placeholders when adding this file to an archive.  The
 expansion depends on the availability of a commit ID, i.e. if
 gitlink:git-archive[1] has been given a tree instead of a commit or a
 tag then no replacement will be done.  The placeholders are the same
-as those for the option `--pretty=format:` of gitlink:git-log[1].
+as those for the option `--pretty=format:` of gitlink:git-log[1],
+except that they need to be wrapped like this: `$Format:PLACEHOLDERS$`
+in the file.  E.g. the string `$Format:%H$` will be replaced by the
+commit hash.
 
 
 GIT

@@ -81,14 +81,58 @@ static int run_remote_archiver(const char *remote, int argc,
 	return !!rv;
 }
 
+static void *format_specfile(const struct commit *commit, const char *format,
+                             unsigned long *sizep)
+{
+	unsigned long len = *sizep, result_len = 0;
+	const char *a = format;
+	char *result = NULL;
+
+	for (;;) {
+		const char *b, *c;
+		char *fmt, *formatted = NULL;
+		unsigned long a_len, fmt_len, formatted_len, allocated = 0;
+
+		b = memmem(a, len, "$Format:", 8);
+		if (!b || a + len < b + 9)
+			break;
+		c = memchr(b + 8, '$', len - 8);
+		if (!c)
+			break;
+
+		a_len = b - a;
+		fmt_len = c - b - 8;
+		fmt = xmalloc(fmt_len + 1);
+		memcpy(fmt, b + 8, fmt_len);
+		fmt[fmt_len] = '\0';
+
+		formatted_len = format_commit_message(commit, fmt, &formatted,
+		                                      &allocated);
+		result = xrealloc(result, result_len + a_len + formatted_len);
+		memcpy(result + result_len, a, a_len);
+		memcpy(result + result_len + a_len, formatted, formatted_len);
+		result_len += a_len + formatted_len;
+		len -= c + 1 - a;
+		a = c + 1;
+	}
+
+	if (result && len) {
+		result = xrealloc(result, result_len + len);
+		memcpy(result + result_len, a, len);
+		result_len += len;
+	}
+
+	*sizep = result_len;
+
+	return result;
+}
+
 static void *convert_to_archive(const char *path,
                                 const void *src, unsigned long *sizep,
                                 const struct commit *commit)
 {
 	static struct git_attr *attr_specfile;
 	struct git_attr_check check[1];
-	char *interpolated = NULL;
-	unsigned long allocated = 0;
 
 	if (!commit)
 		return NULL;

@@ -102,9 +146,7 @@ static void *convert_to_archive(const char *path,
 	if (!ATTR_TRUE(check[0].value))
 		return NULL;
 
-	*sizep = format_commit_message(commit, src, &interpolated, &allocated);
-
-	return interpolated;
+	return format_specfile(commit, src, sizep);
 }
 
 void *sha1_file_to_archive(const char *path, const unsigned char *sha1,

@@ -36,7 +36,7 @@ test_expect_success \
      echo simple textfile >a/a &&
      mkdir a/bin &&
      cp /bin/sh a/bin &&
-     printf "%s" "$SPECFILEFORMAT" >a/specfile &&
+     printf "A\$Format:%s\$O" "$SPECFILEFORMAT" >a/specfile &&
      ln -s a a/l1 &&
      (p=long_path_to_a_file && cd a &&
       for depth in 1 2 3 4 5; do mkdir $p && cd $p; done &&

@@ -119,7 +119,7 @@ test_expect_success \
 
 test_expect_success \
      'validate specfile contents' \
-     'git log --max-count=1 "--pretty=format:$SPECFILEFORMAT" HEAD \
+     'git log --max-count=1 "--pretty=format:A${SPECFILEFORMAT}O" HEAD \
       >f/a/specfile.expected &&
       diff f/a/specfile.expected f/a/specfile'