From 93edebc81c6ef81dc4e4e20d567fa26a1182e67f Mon Sep 17 00:00:00 2001
From: Yorhel <git@yorhel.nl>
Date: Fri, 15 Nov 2024 15:17:21 +0100
Subject: [PATCH] Expand ~ and ~user in config file

Fixes #243
---
 src/main.c | 16 ++++++++++------
 src/util.c | 42 +++++++++++++++++++++++++++++++++++++++++-
 src/util.h |  2 ++
 3 files changed, 53 insertions(+), 7 deletions(-)

diff --git a/src/main.c b/src/main.c
index 5ba66cd..b6bad44 100644
--- a/src/main.c
+++ b/src/main.c
@@ -191,7 +191,7 @@ static char *argparser_arg(struct argparser *p) {
 #define OPT(_s) (strcmp(argparser_state.last, (_s)) == 0)
 #define ARG (argparser_arg(&argparser_state))
 
-static int arg_option(void) {
+static int arg_option(int infile) {
   char *arg, *tmp;
   if(OPT("-q") || OPT("--slow-ui-updates")) update_delay = 2000;
   else if(OPT("--fast-ui-updates")) update_delay = 100;
@@ -253,10 +253,14 @@ static int arg_option(void) {
   else if(OPT("--no-si")) si = 0;
   else if(OPT("-L") || OPT("--follow-symlinks")) follow_symlinks = 1;
   else if(OPT("--no-follow-symlinks")) follow_symlinks = 0;
-  else if(OPT("--exclude")) exclude_add(ARG);
-  else if(OPT("-X") || OPT("--exclude-from")) {
-    arg = ARG;
+  else if(OPT("--exclude")) {
+    arg = infile ? expanduser(ARG) : ARG;
+    exclude_add(arg);
+    if(infile) free(arg);
+  } else if(OPT("-X") || OPT("--exclude-from")) {
+    arg = infile ? expanduser(ARG) : ARG;
     if(exclude_addfile(arg)) die("Can't open %s: %s\n", arg, strerror(errno));
+    if(infile) free(arg);
   } else if(OPT("--exclude-caches")) cachedir_tags = 1;
   else if(OPT("--include-caches")) cachedir_tags = 0;
   else if(OPT("--exclude-kernfs")) exclude_kernfs = 1;
@@ -347,7 +351,7 @@ static void config_read(const char *fn) {
   argparser_state.argc = argslen;
 
   while((r = argparser_next(&argparser_state)) > 0)
-    if(r == 2 || !arg_option())
+    if(r == 2 || !arg_option(1))
       die("Unknown option in config file '%s': %s.\nRun with --ignore-config to skip reading config files.\n", fn, argparser_state.last);
 
   for(argsi=args; argsi && *argsi; argsi++) free(*argsi);
@@ -394,7 +398,7 @@ static void argv_parse(int argc, char **argv) {
     else if(OPT("-o")) export = ARG;
     else if(OPT("-f")) import = ARG;
     else if(OPT("--ignore-config")) {}
-    else if(!arg_option()) die("Unknown option '%s'.\n", argparser_state.last);
+    else if(!arg_option(0)) die("Unknown option '%s'.\n", argparser_state.last);
   }
 
 #if !(HAVE_LINUX_MAGIC_H && HAVE_SYS_STATFS_H && HAVE_STATFS)
diff --git a/src/util.c b/src/util.c
index e387d74..6b36b9b 100644
--- a/src/util.c
+++ b/src/util.c
@@ -30,6 +30,8 @@
 #include <ncurses.h>
 #include <stdarg.h>
 #include <unistd.h>
+#include <pwd.h>
+
 #ifdef HAVE_LOCALE_H
 #include <locale.h>
 #endif
@@ -441,7 +443,7 @@ void addparentstats(struct dir *d, int64_t size, int64_t asize, uint64_t mtime,
   char buf[128];\
   while((ptr = f) == NULL) {\
     close_nc();\
-    write(2, oom_msg, sizeof(oom_msg));\
+    write(2, oom_msg, sizeof(oom_msg)-1);\
     read(0, buf, sizeof(buf));\
   }\
   return ptr;
@@ -455,3 +457,41 @@ char *xstrdup(const char *str) {
   strcpy(r, str);
   return r;
 }
+
+
+/* Expands '~' and '~user' */
+char *expanduser(const char *path) {
+  size_t len, size;
+  struct passwd *pwd;
+  char *home = NULL, *tmp;
+
+  if(path[0] != '~') return xstrdup(path);
+  len = strcspn(path+1, "/");
+
+  if(len == 0) {
+    home = getenv("HOME");
+    if(!home) {
+      pwd = getpwuid(getuid());
+      if(pwd) home = pwd->pw_dir;
+    }
+  } else {
+    tmp = xmalloc(len+1);
+    memcpy(tmp, path+1, len);
+    tmp[len] = 0;
+    pwd = getpwnam(tmp);
+    free(tmp);
+    if(pwd) home = pwd->pw_dir;
+  }
+  if(!home) return xstrdup(path);
+
+  size = strlen(home);
+  while(size > 0 && home[size-1] == '/') size--;
+  home[size] = 0;
+
+  if(size == 0 && path[len+1] == 0) return xstrdup("/");
+
+  size += strlen(path) - len;
+  tmp = xmalloc(size);
+  snprintf(tmp, size, "%s%s", home, path+1+len);
+  return tmp;
+}
diff --git a/src/util.h b/src/util.h
index fe01dc6..2b03fd3 100644
--- a/src/util.h
+++ b/src/util.h
@@ -190,5 +190,7 @@ void *xrealloc(void *, size_t);
 
 char *xstrdup(const char *);
 
+char *expanduser(const char *);
+
 #endif