X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=libi3%2Fget_exe_path.c;h=e933f5b62a10e1ae0fef263b32f7125aa8ccbd7a;hb=aa0b1f599f25cfe858ebbc7fa80d459bcdb2ae02;hp=fca7ba02cf5a5f3fa2787c55062b89b76ab4c0d5;hpb=75206db3a1aeb0b348e6220251de9a95966d5130;p=i3%2Fi3

diff --git a/libi3/get_exe_path.c b/libi3/get_exe_path.c
index fca7ba02..e933f5b6 100644
--- a/libi3/get_exe_path.c
+++ b/libi3/get_exe_path.c
@@ -1,74 +1,107 @@
+/*
+ * vim:ts=4:sw=4:expandtab
+ *
+ * i3 - an improved dynamic tiling window manager
+ * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
+ *
+ */
+#include "libi3.h"
+
 #include <unistd.h>
 #include <string.h>
 #include <stdio.h>
 #include <limits.h>
 #include <stdlib.h>
-
-#include "libi3.h"
+#include <errno.h>
 
 /*
  * This function returns the absolute path to the executable it is running in.
  *
- * The implementation follows http://stackoverflow.com/a/933996/712014
+ * The implementation follows https://stackoverflow.com/a/933996/712014
  *
+ * Returned value must be freed by the caller.
  */
-const char *get_exe_path(const char *argv0) {
-	static char destpath[PATH_MAX];
-	char tmp[PATH_MAX];
+char *get_exe_path(const char *argv0) {
+    size_t destpath_size = 1024;
+    size_t tmp_size = 1024;
+    char *destpath = smalloc(destpath_size);
+    char *tmp = smalloc(tmp_size);
 
 #if defined(__linux__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
-	/* Linux and Debian/kFreeBSD provide /proc/self/exe */
+/* Linux and Debian/kFreeBSD provide /proc/self/exe */
 #if defined(__linux__) || defined(__FreeBSD_kernel__)
-	const char *exepath = "/proc/self/exe";
+    const char *exepath = "/proc/self/exe";
 #elif defined(__FreeBSD__)
-	const char *exepath = "/proc/curproc/file";
+    const char *exepath = "/proc/curproc/file";
 #endif
-	ssize_t linksize;
-
-	if ((linksize = readlink(exepath, destpath, sizeof(destpath) - 1)) != -1) {
-		/* readlink() does not NULL-terminate strings, so we have to. */
-		destpath[linksize] = '\0';
+    ssize_t linksize;
 
-		return destpath;
-	}
+    while ((linksize = readlink(exepath, destpath, destpath_size)) == (ssize_t)destpath_size) {
+        destpath_size = destpath_size * 2;
+        destpath = srealloc(destpath, destpath_size);
+    }
+    if (linksize != -1) {
+        /* readlink() does not NULL-terminate strings, so we have to. */
+        destpath[linksize] = '\0';
+        free(tmp);
+        return destpath;
+    }
 #endif
 
-	/* argv[0] is most likely a full path if it starts with a slash. */
-	if (argv0[0] == '/')
-		return argv0;
+    /* argv[0] is most likely a full path if it starts with a slash. */
+    if (argv0[0] == '/') {
+        free(tmp);
+        free(destpath);
+        return sstrdup(argv0);
+    }
 
-	/* if argv[0] contains a /, prepend the working directory */
-	if (strchr(argv0, '/') != NULL &&
-		getcwd(tmp, sizeof(tmp)) != NULL) {
-		snprintf(destpath, sizeof(destpath), "%s/%s", tmp, argv0);
-		return destpath;
-	}
+    /* if argv[0] contains a /, prepend the working directory */
+    if (strchr(argv0, '/') != NULL) {
+        char *retgcwd;
+        while ((retgcwd = getcwd(tmp, tmp_size)) == NULL && errno == ERANGE) {
+            tmp_size = tmp_size * 2;
+            tmp = srealloc(tmp, tmp_size);
+        }
+        if (retgcwd != NULL) {
+            free(destpath);
+            sasprintf(&destpath, "%s/%s", tmp, argv0);
+            free(tmp);
+            return destpath;
+        }
+    }
 
-	/* Fall back to searching $PATH (or _CS_PATH in absence of $PATH). */
-	char *path = getenv("PATH");
-	if (path == NULL) {
-		/* _CS_PATH is typically something like "/bin:/usr/bin" */
-		confstr(_CS_PATH, tmp, sizeof(tmp));
-		sasprintf(&path, ":%s", tmp);
-	} else {
-		path = strdup(path);
-	}
-	const char *component;
-	char *str = path;
-	while (1) {
-		if ((component = strtok(str, ":")) == NULL)
-			break;
-		str = NULL;
-		snprintf(destpath, sizeof(destpath), "%s/%s", component, argv0);
-		/* Of course this is not 100% equivalent to actually exec()ing the
+    /* Fall back to searching $PATH (or _CS_PATH in absence of $PATH). */
+    char *path = getenv("PATH");
+    if (path == NULL) {
+        /* _CS_PATH is typically something like "/bin:/usr/bin" */
+        while (confstr(_CS_PATH, tmp, tmp_size) > tmp_size) {
+            tmp_size = tmp_size * 2;
+            tmp = srealloc(tmp, tmp_size);
+        }
+        sasprintf(&path, ":%s", tmp);
+    } else {
+        path = sstrdup(path);
+    }
+    const char *component;
+    char *str = path;
+    while (1) {
+        if ((component = strtok(str, ":")) == NULL)
+            break;
+        str = NULL;
+        free(destpath);
+        sasprintf(&destpath, "%s/%s", component, argv0);
+        /* Of course this is not 100% equivalent to actually exec()ing the
 		 * binary, but meh. */
-		if (access(destpath, X_OK) == 0) {
-			free(path);
-			return destpath;
-		}
-	}
-	free(path);
+        if (access(destpath, X_OK) == 0) {
+            free(path);
+            free(tmp);
+            return destpath;
+        }
+    }
+    free(destpath);
+    free(path);
+    free(tmp);
 
-	/* Last resort: maybe it’s in /usr/bin? */
-	return "/usr/bin/i3-nagbar";
+    /* Last resort: maybe it’s in /usr/bin? */
+    return sstrdup("/usr/bin/i3-nagbar");
 }