rng-egd: remove redundant free

[qemu.git] / util / cutils.c

diff --git a/util/cutils.c b/util/cutils.c
index 1439da4f9915fe7fb12336cc2ce360d4f8d7554a..0116fcde74f197f0d41b2f393c9fd7ae4c9de073 100644 (file)
--- a/util/cutils.c
+++ b/util/cutils.c
@@ -107,6 +107,27 @@ int qemu_strnlen(const char *s, int max_len)
     return i;
 }
 
+char *qemu_strsep(char **input, const char *delim)
+{
+    char *result = *input;
+    if (result != NULL) {
+        char *p;
+
+        for (p = result; *p != '\0'; p++) {
+            if (strchr(delim, *p)) {
+                break;
+            }
+        }
+        if (*p == '\0') {
+            *input = NULL;
+        } else {
+            *p = '\0';
+            *input = p + 1;
+        }
+    }
+    return result;
+}
+
 time_t mktimegm(struct tm *tm)
 {
     time_t t;
@@ -142,6 +163,61 @@ int qemu_fdatasync(int fd)
 #endif
 }
 
+/*
+ * Searches for an area with non-zero content in a buffer
+ *
+ * Attention! The len must be a multiple of
+ * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR * sizeof(VECTYPE)
+ * and addr must be a multiple of sizeof(VECTYPE) due to
+ * restriction of optimizations in this function.
+ *
+ * can_use_buffer_find_nonzero_offset() can be used to check
+ * these requirements.
+ *
+ * The return value is the offset of the non-zero area rounded
+ * down to a multiple of sizeof(VECTYPE) for the first
+ * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR chunks and down to
+ * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR * sizeof(VECTYPE)
+ * afterwards.
+ *
+ * If the buffer is all zero the return value is equal to len.
+ */
+
+size_t buffer_find_nonzero_offset(const void *buf, size_t len)
+{
+    const VECTYPE *p = buf;
+    const VECTYPE zero = (VECTYPE){0};
+    size_t i;
+
+    assert(can_use_buffer_find_nonzero_offset(buf, len));
+
+    if (!len) {
+        return 0;
+    }
+
+    for (i = 0; i < BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR; i++) {
+        if (!ALL_EQ(p[i], zero)) {
+            return i * sizeof(VECTYPE);
+        }
+    }
+
+    for (i = BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR;
+         i < len / sizeof(VECTYPE);
+         i += BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR) {
+        VECTYPE tmp0 = p[i + 0] | p[i + 1];
+        VECTYPE tmp1 = p[i + 2] | p[i + 3];
+        VECTYPE tmp2 = p[i + 4] | p[i + 5];
+        VECTYPE tmp3 = p[i + 6] | p[i + 7];
+        VECTYPE tmp01 = tmp0 | tmp1;
+        VECTYPE tmp23 = tmp2 | tmp3;
+        if (!ALL_EQ(tmp01 | tmp23, zero)) {
+            break;
+        }
+    }
+
+    return i * sizeof(VECTYPE);
+}
+
 /*
  * Checks if a buffer is all zeroes
  *
@@ -160,6 +236,11 @@ bool buffer_is_zero(const void *buf, size_t len)
     long d0, d1, d2, d3;
     const long * const data = buf;
 
+    /* use vector optimized zero check if possible */
+    if (can_use_buffer_find_nonzero_offset(buf, len)) {
+        return buffer_find_nonzero_offset(buf, len) == len;
+    }
+
     assert(len % (4 * sizeof(long)) == 0);
     len /= sizeof(long);
 
@@ -207,6 +288,10 @@ static int64_t suffix_mul(char suffix, int64_t unit)
         return unit * unit * unit;
     case STRTOSZ_DEFSUFFIX_TB:
         return unit * unit * unit * unit;
+    case STRTOSZ_DEFSUFFIX_PB:
+        return unit * unit * unit * unit * unit;
+    case STRTOSZ_DEFSUFFIX_EB:
+        return unit * unit * unit * unit * unit * unit;
     }
     return -1;
 }
@@ -422,3 +507,26 @@ int uleb128_decode_small(const uint8_t *in, uint32_t *n)
         return 2;
     }
 }
+
+/*
+ * helper to parse debug environment variables
+ */
+int parse_debug_env(const char *name, int max, int initial)
+{
+    char *debug_env = getenv(name);
+    char *inv = NULL;
+    int debug;
+
+    if (!debug_env) {
+        return initial;
+    }
+    debug = strtol(debug_env, &inv, 10);
+    if (inv == debug_env) {
+        return initial;
+    }
+    if (debug < 0 || debug > max) {
+        fprintf(stderr, "warning: %s not in [0, %d]", name, max);
+        return initial;
+    }
+    return debug;
+}