[Updated] D9006: chg: make is possible to call by default an hg binary located next to chg

[valentin.gatienbaron (Valentin Gatien-Baron)]

Closed by commit rHGeb443f7cbc2c: chg: make is possible to call by default an hg binary located next to chg (authored by valentin.gatienbaron).
This revision was automatically updated to reflect the committed changes.

REPOSITORY
  rHG Mercurial

CHANGES SINCE LAST UPDATE
  https://phab.mercurial-scm.org/D9006?vs=22676&id=22826

CHANGES SINCE LAST ACTION
  https://phab.mercurial-scm.org/D9006/new/

REVISION DETAIL
  https://phab.mercurial-scm.org/D9006

AFFECTED FILES
  contrib/chg/Makefile
  contrib/chg/README
  contrib/chg/chg.c

CHANGE DETAILS

diff --git a/contrib/chg/chg.c b/contrib/chg/chg.c
--- a/contrib/chg/chg.c
+++ b/contrib/chg/chg.c
@@ -184,13 +184,46 @@
 		abortmsg("too long TMPDIR or CHGSOCKNAME (r = %d)", r);
 }
 
+/* If the current program is, say, /a/b/c/chg, returns /a/b/c/hg. */
+static char *getrelhgcmd(void)
+{
+	ssize_t n;
+	char *res, *slash;
+	int maxsize = 4096;
+	res = malloc(maxsize);
+	if (res == NULL)
+		goto cleanup;
+	n = readlink("/proc/self/exe", res, maxsize);
+	if (n < 0 || n >= maxsize)
+		goto cleanup;
+	res[n] = '\0';
+	slash = strrchr(res, '/');
+	if (slash == NULL)
+		goto cleanup;
+	/* 4 is strlen("/hg") + nul byte */
+	if (slash + 4 >= res + maxsize)
+		goto cleanup;
+	memcpy(slash, "/hg", 4);
+	return res;
+ cleanup:
+	free(res);
+	return NULL;
+}
+
 static const char *gethgcmd(void)
 {
 	static const char *hgcmd = NULL;
+#ifdef HGPATHREL
+	int tryrelhgcmd = 1;
+#else
+	int tryrelhgcmd = 0;
+#endif
 	if (!hgcmd) {
 		hgcmd = getenv("CHGHG");
 		if (!hgcmd || hgcmd[0] == '\0')
 			hgcmd = getenv("HG");
+		if (tryrelhgcmd && (!hgcmd || hgcmd[0] == '\0'))
+			hgcmd = getrelhgcmd();
 		if (!hgcmd || hgcmd[0] == '\0')
 #ifdef HGPATH
 			hgcmd = (HGPATH);
diff --git a/contrib/chg/README b/contrib/chg/README
--- a/contrib/chg/README
+++ b/contrib/chg/README
@@ -30,3 +30,11 @@
  * CHGSOCKNAME specifies the socket path of the background cmdserver.
  * CHGTIMEOUT specifies how many seconds chg will wait before giving up
    connecting to a cmdserver. If it is 0, chg will wait forever. Default: 60
+
+Build environment variables:
+
+ * HGPATH: the path to the hg executable to call when CHGHG and HG are not set,
+   instead of "hg"
+ * HGPATHREL=1: when CHGHG and HG are not set, the hg executable will be ./hg
+   relative to the chg executable. Only works on linux, falls back to "hg"
+   otherwise.
diff --git a/contrib/chg/Makefile b/contrib/chg/Makefile
--- a/contrib/chg/Makefile
+++ b/contrib/chg/Makefile
@@ -8,6 +8,9 @@
 ifdef HGPATH
 override CPPFLAGS += -DHGPATH=\"$(HGPATH)\"
 endif
+ifdef HGPATHREL
+override CPPFLAGS += -DHGPATHREL=\"$(HGPATHREL)\"
+endif
 
 DESTDIR =
 PREFIX = /usr/local



To: valentin.gatienbaron, #hg-reviewers, marmoute, pulkit
Cc: marmoute, pulkit, yuja, mercurial-patches
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mercurial-scm.org/pipermail/mercurial-patches/attachments/20200924/41d4723c/attachment-0002.html>