mercurial/exewrapper.c
author the31k <the31k@thethirty.one>
Thu, 31 Aug 2017 18:24:08 +0300
changeset 34091 abf91c4f9608
parent 31452 0241dd94ed38
child 34636 31c6c4d27be7
permissions -rw-r--r--
branches: correctly show inactive multiheaded branches Issue being fixed here: `hg branches` incorrectly renders inactive multiheaded branches as active if they have closed heads. Example: ``` $ hg log --template '{rev}:{node|short} "{desc}" ({branch}) [parents: {parents}]\n' 4:2e2fa7af8357 "merge" (default) [parents: 0:c94e548c8c7d 3:7be622ae5832 ] 3:7be622ae5832 "2" (somebranch) [parents: 1:81c1d9458987 ] 2:be82cf30409c "close" (somebranch) [parents: ] 1:81c1d9458987 "1" (somebranch) [parents: ] 0:c94e548c8c7d "initial" (default) [parents: ] $ hg branches default 4:2e2fa7af8357 somebranch 3:7be622ae5832 ``` Branch `somebranch` have two heads, the 1st one being closed (rev 2) and the other one being merged into default (rev 3). This branch should be shown as inactive one. This happens because we intersect branch heads with repo heads to check branch activity. In this case intersection in a set with one node (rev 2). This head is closed but the branch is marked as active nevertheless. Fix is to check branch activity by intersecting only open heads set. Fixed output: ``` $ hg branches default 4:2e2fa7af8357 somebranch 3:7be622ae5832 (inactive) ``` Relevant tests for multihead branches added to test-branches suite. Implentation note about adding `iteropen` method: At first I have tried to modify `iterbranches` is such a way that it would filter out closed heads itself. For example it could have `closed=False` parameter. But in this case we would have to filter closed tips as well. Reasoning in terms of `hg branches` we actually are not allowed to do this. Also, we need to do heads filtering only if tip is not closed itself. But if it is - we are ok to skip filtering, because branch is already known to be inactive. So we can't implement heads filtering in `iterbranches` in elegant way, because we will end up with something like `closed_heads=False` or even `closed_heads_is_tip_is_open`. Finally I decided to move this logic to the `branches` function, adding `iteropen` helper method. Differential Revision: https://phab.mercurial-scm.org/D583

/*
 exewrapper.c - wrapper for calling a python script on Windows

 Copyright 2012 Adrian Buehlmann <adrian@cadifra.com> and others

 This software may be used and distributed according to the terms of the
 GNU General Public License version 2 or any later version.
*/

#include <stdio.h>
#include <windows.h>

#include "hgpythonlib.h"

#ifdef __GNUC__
int strcat_s(char *d, size_t n, const char *s)
{
	return !strncat(d, s, n);
}
int strcpy_s(char *d, size_t n, const char *s)
{
	return !strncpy(d, s, n);
}
#endif


static char pyscript[MAX_PATH + 10];
static char pyhome[MAX_PATH + 10];
static char envpyhome[MAX_PATH + 10];
static char pydllfile[MAX_PATH + 10];

int main(int argc, char *argv[])
{
	char *p;
	int ret;
	int i;
	int n;
	char **pyargv;
	WIN32_FIND_DATA fdata;
	HANDLE hfind;
	const char *err;
	HMODULE pydll;
	void (__cdecl *Py_SetPythonHome)(char *home);
	int (__cdecl *Py_Main)(int argc, char *argv[]);

	if (GetModuleFileName(NULL, pyscript, sizeof(pyscript)) == 0)
	{
		err = "GetModuleFileName failed";
		goto bail;
	}

	p = strrchr(pyscript, '.');
	if (p == NULL) {
		err = "malformed module filename";
		goto bail;
	}
	*p = 0; /* cut trailing ".exe" */
	strcpy_s(pyhome, sizeof(pyhome), pyscript);

	hfind = FindFirstFile(pyscript, &fdata);
	if (hfind != INVALID_HANDLE_VALUE) {
		/* pyscript exists, close handle */
		FindClose(hfind);
	} else {
		/* file pyscript isn't there, take <pyscript>exe.py */
		strcat_s(pyscript, sizeof(pyscript), "exe.py");
	}

	pydll = NULL;

	p = strrchr(pyhome, '\\');
	if (p == NULL) {
		err = "can't find backslash in module filename";
		goto bail;
	}
	*p = 0; /* cut at directory */

	/* check for private Python of HackableMercurial */
	strcat_s(pyhome, sizeof(pyhome), "\\hg-python");

	hfind = FindFirstFile(pyhome, &fdata);
	if (hfind != INVALID_HANDLE_VALUE) {
		/* Path .\hg-python exists. We are probably in HackableMercurial
		scenario, so let's load python dll from this dir. */
		FindClose(hfind);
		strcpy_s(pydllfile, sizeof(pydllfile), pyhome);
		strcat_s(pydllfile, sizeof(pydllfile), "\\" HGPYTHONLIB ".dll");
		pydll = LoadLibrary(pydllfile);
		if (pydll == NULL) {
			err = "failed to load private Python DLL " HGPYTHONLIB ".dll";
			goto bail;
		}
		Py_SetPythonHome = (void*)GetProcAddress(pydll, "Py_SetPythonHome");
		if (Py_SetPythonHome == NULL) {
			err = "failed to get Py_SetPythonHome";
			goto bail;
		}
		Py_SetPythonHome(pyhome);
	}

	if (pydll == NULL) {
		pydll = LoadLibrary(HGPYTHONLIB ".dll");
		if (pydll == NULL) {
			err = "failed to load Python DLL " HGPYTHONLIB ".dll";
			goto bail;
		}
	}

	Py_Main = (void*)GetProcAddress(pydll, "Py_Main");
	if (Py_Main == NULL) {
		err = "failed to get Py_Main";
		goto bail;
	}

	/*
	Only add the pyscript to the args, if it's not already there. It may
	already be there, if the script spawned a child process of itself, in
	the same way as it got called, that is, with the pyscript already in
	place. So we optionally accept the pyscript as the first argument
	(argv[1]), letting our exe taking the role of the python interpreter.
	*/
	if (argc >= 2 && strcmp(argv[1], pyscript) == 0) {
		/*
		pyscript is already in the args, so there is no need to copy
		the args and we can directly call the python interpreter with
		the original args.
		*/
		return Py_Main(argc, argv);
	}

	/*
	Start assembling the args for the Python interpreter call. We put the
	name of our exe (argv[0]) in the position where the python.exe
	canonically is, and insert the pyscript next.
	*/
	pyargv = malloc((argc + 5) * sizeof(char*));
	if (pyargv == NULL) {
		err = "not enough memory";
		goto bail;
	}
	n = 0;
	pyargv[n++] = argv[0];
	pyargv[n++] = pyscript;

	/* copy remaining args from the command line */
	for (i = 1; i < argc; i++)
		pyargv[n++] = argv[i];
	/* argv[argc] is guaranteed to be NULL, so we forward that guarantee */
	pyargv[n] = NULL;

	ret = Py_Main(n, pyargv); /* The Python interpreter call */

	free(pyargv);
	return ret;

bail:
	fprintf(stderr, "abort: %s\n", err);
	return 255;
}