Clean up temp cache dir handling.

Allow temp dir setting via specific env variable to point to fast devices like ramdisk,ssd.

main.c

@@ -1730,6 +1730,7 @@ start_compress(const char *filename, uint64_t chunksize, int level)
 
 	/* A host of sanity checks. */
 	if (!pipe_mode) {
+		char *tmp;
 		if ((uncompfd = open(filename, O_RDWR, 0)) == -1)
 			err_exit(1, "Cannot open: %s", filename);
 
@@ -1786,7 +1787,13 @@ start_compress(const char *filename, uint64_t chunksize, int level)
 		 */
 		strcpy(tmpfile1, filename);
 		strcpy(tmpfile1, dirname(tmpfile1));
-		strcpy(tmpdir, tmpfile1);
+
+		tmp = getenv("PCOMPRESS_CACHE_DIR");
+		if (tmp == NULL || !chk_dir(tmp)) {
+			strcpy(tmpdir, tmpfile1);
+		} else {
+			strcpy(tmpdir, tmp);
+		}
 		strcat(tmpfile1, "/.pcompXXXXXX");
 		snprintf(to_filename, sizeof (to_filename), "%s" COMP_EXTN, filename);
 		if ((compfd = mkstemp(tmpfile1)) == -1) {
@@ -1798,7 +1805,6 @@ start_compress(const char *filename, uint64_t chunksize, int level)
 		signal(SIGTERM, Int_Handler);
 	} else {
 		char *tmp;
-		struct stat st;
 
 		/*
 		 * Use stdin/stdout for pipe mode.
@@ -1817,29 +1823,20 @@ start_compress(const char *filename, uint64_t chunksize, int level)
 		/*
 		 * Get a workable temporary dir. Required if global dedupe is enabled.
 		 */
-		tmp = getenv("TMPDIR");
-		if (tmp == NULL) {
-			tmp = getenv("HOME");
-			if (tmp == NULL) {
-				if (getcwd(tmpdir, MAXPATHLEN) == NULL) {
-					tmp = "/tmp";
-				} else {
-					tmp = tmpdir;
+		tmp = getenv("PCOMPRESS_CACHE_DIR");
+		if (tmp == NULL || !chk_dir(tmp)) {
+			tmp = getenv("TMPDIR");
+			if (tmp == NULL || !chk_dir(tmp)) {
+				tmp = getenv("HOME");
+				if (tmp == NULL || !chk_dir(tmp)) {
+					if (getcwd(tmpdir, MAXPATHLEN) == NULL) {
+						tmp = "/tmp";
+					} else {
+						tmp = tmpdir;
+					}
 				}
 			}
 		}
-		if (stat(tmp, &st) == -1) {
-			fprintf(stderr, "Unable to find writable temporary dir.\n");
-			COMP_BAIL;
-		}
-		if (!S_ISDIR(st.st_mode)) {
-			if (strcmp(tmp, "/tmp") != 0) {
-				tmp = "/tmp";
-			} else {
-				fprintf(stderr, "Unable to find writable temporary dir.\n");
-				COMP_BAIL;
-			}
-		}
 		strcpy(tmpdir, tmp);
 	}
 

rabin/global/dedupe_config.c

@@ -382,7 +382,6 @@ set_config_s(archive_config_t *cfg, const char *algo, cksum_t ck, cksum_t ck_sim
 	}
 
 	cfg->segment_sz = cfg->segment_sz_bytes / cfg->chunk_sz_bytes;
-
 	return (0);
 }
 

rabin/global/index.c

@@ -181,8 +181,8 @@ set_cfg:
 	*memreqd = MEM_REQD(*hash_slots, *hash_entry_size);
 
 	/*
-	 * If memory required is more than twice the indicated memory limit then
-	 * we switch to Segmented Cumulative Similarity based dedupe.
+	 * If memory required is more than thrice the indicated memory limit then
+	 * we switch to Segmented Similarity based dedupe.
 	 */
 	if (*memreqd > (memlimit * 3) && cfg->dedupe_mode == MODE_SIMPLE &&
 	    *pct_interval == 0 && tmppath != NULL) {

utils/utils.c

@@ -24,6 +24,7 @@
  */
 
 #include <sys/types.h>
+#include <sys/stat.h>
 #include <sys/param.h>
 #include <sys/time.h>
 #include <fcntl.h>
@@ -406,3 +407,17 @@ get_sys_limits(my_sysinfo *msys_info)
 		msys_info->freeram = (msys_info->freeram >> 1) + (msys_info->freeram >> 2);
 	}
 }
+
+int
+chk_dir(char *dir)
+{
+	struct stat st;
+
+	if (stat(dir, &st) == -1) {
+		return (0);
+	}
+	if (!S_ISDIR(st.st_mode)) {
+		return (0);
+	}
+	return (1);
+}

utils/utils.h

@@ -219,6 +219,7 @@ extern uint64_t get_total_ram();
 extern double get_wtime_millis(void);
 extern double get_mb_s(uint64_t bytes, double strt, double en);
 extern void get_sys_limits(my_sysinfo *msys_info);
+extern int chk_dir(char *dir);
 extern void init_algo_props(algo_props_t *props);
 extern void init_pcompress();