From 1c6b5ace1642b6abb511cdf620e181476132067a Mon Sep 17 00:00:00 2001
From: Natalia Serrano <natalia.serrano@qindel.com>
Date: Thu, 30 Jan 2025 17:05:21 +0100
Subject: [PATCH] refs #1415 add ogGetCacheSpace, fix a bug

---
 client/lib/engine/bin/CacheLib.py       | 82 ++++++++++++++-----------
 client/shared/functions/ogGetCacheSpace | 13 ++++
 2 files changed, 59 insertions(+), 36 deletions(-)
 create mode 100755 client/shared/functions/ogGetCacheSpace

diff --git a/client/lib/engine/bin/CacheLib.py b/client/lib/engine/bin/CacheLib.py
index 575457b..d2303b1 100755
--- a/client/lib/engine/bin/CacheLib.py
+++ b/client/lib/engine/bin/CacheLib.py
@@ -193,46 +193,51 @@ def ogGetCacheSize():
 #@note    El espacio disponible es el que hay entre el límite superior de la partición 3 del disco 1 y el final de dicho disco, y no puede ser superior a la mitad de dicho disco.
 #*/ ##
 def ogGetCacheSpace():
-    """
-    Obtiene el espacio libre en la partición de caché en kilobytes.
-
-    :return: Espacio libre en kilobytes.
-    :raises RuntimeError: Si ocurre un error al obtener el espacio libre.
-    """
-    # Si se solicita, mostrar ayuda.
-    if len(sys.argv) > 1 and sys.argv[1] == "help":
-        ogHelp("ogGetCacheSpace", "help", "ogGetCacheSpace")
-
-    # Error si no se encuentra partición de caché.
     cachepart = ogFindCache()
-    if cachepart is None:
-        raise RuntimeError(MSG_NOCACHE)
+    if not cachepart:
+        SystemLib.ogRaiseError ([], ogGlobals.OG_ERR_PARTITION, ogGlobals.lang.MSG_NOCACHE)
+        return None
+    cachepart = cachepart.split()
 
-    # Obtener el tamaño del disco y el número de sectores.
-    disk = ogDiskToDev(cachepart)
-    try:
-        result = subprocess.run(["sfdisk", "-g", disk], capture_output=True, text=True, check=True)
-        output = result.stdout
-        sectors_per_cylinder = int(output.splitlines()[1].split()[1])
-        total_sectors = int(output.splitlines()[1].split()[0]) * sectors_per_cylinder - 1
-    except subprocess.CalledProcessError as e:
-        raise RuntimeError(f"Error al obtener el espacio libre: {e}")
+    disk = DiskLib.ogDiskToDev (cachepart[0])
+    if not disk:
+        return None
 
-    # Obtener el último sector de la partición 3.
-    try:
-        result = subprocess.run(["sfdisk", "-uS", "-l", disk], capture_output=True, text=True, check=True)
-        output = result.stdout
-        end_sector_part3 = int([line.split()[2] for line in output.splitlines() if cachepart + "3" in line][0])
-    except subprocess.CalledProcessError as e:
-        raise RuntimeError(f"Error al obtener el espacio libre: {e}")
+    sectors = 0
+    disk_bn = os.path.basename (disk)
+    with open ('/proc/partitions', 'r') as fd:
+        proc_parts = fd.read()
+    for l in proc_parts.splitlines():
+        items = l.split()
+        if len(items) < 4: continue
+        if items[3] == disk_bn:
+            sectors = 2 * int (items[2])
+    if not sectors: return None
 
-    # Calcular el espacio libre en kilobytes.
-    if end_sector_part3 > total_sectors // 2:
-        free_space_kb = (total_sectors - end_sector_part3) // 2
+    sfdisk_out = subprocess.run (['sfdisk', '-g', disk], capture_output=True, text=True).stdout
+    cyls = int (sfdisk_out.split()[1])
+    sectors = sectors/cyls * cyls - 1
+
+    ## the original code has a hard dependency on the existence of a third partition
+    ## if the disk has sda1, sda2 and sda4, the code fails.
+    ## this is an improved version
+    endpart3 = 0
+    for trypart in [3, 2, 1]:
+        sfdisk_out = subprocess.run (['sfdisk', '-uS', '-l', disk], capture_output=True, text=True).stdout
+        for l in sfdisk_out.splitlines():
+            items = l.split()
+            if len(items) < 6: continue
+            if f'{disk}{trypart}' == items[0]:
+                endpart3 = int (items[2])
+                break
+        if endpart3: break
+    if not endpart3: return None
+
+# Mostrar espacio libre en KB (1 KB = 2 sectores)
+    if endpart3 > sectors // 2:
+        return (sectors - endpart3) // 2
     else:
-        free_space_kb = total_sectors // 4
-
-    return free_space_kb
+        return sectors // 4
 
 
 #/**
@@ -243,7 +248,12 @@ def ogGetCacheSpace():
 #@warning Salidas de errores no determinada
 #*/ ##
 def ogMountCache():
-    c = ogFindCache().split()
+    c = ogFindCache()
+    if not c:
+        SystemLib.ogRaiseError ([], ogGlobals.OG_ERR_PARTITION, ogGlobals.lang.MSG_NOCACHE)
+        return None
+
+    c = c.split()
     m = FileSystemLib.ogMountFs (c[0], c[1])
     if not m:
         SystemLib.ogRaiseError ([], ogGlobals.OG_ERR_PARTITION, ogGlobals.lang.MSG_NOCACHE)
diff --git a/client/shared/functions/ogGetCacheSpace b/client/shared/functions/ogGetCacheSpace
new file mode 100755
index 0000000..2e5dce3
--- /dev/null
+++ b/client/shared/functions/ogGetCacheSpace
@@ -0,0 +1,13 @@
+#!/usr/bin/python3
+
+import sys
+import argparse
+from SystemLib import ogHelp
+from CacheLib import ogGetCacheSpace
+
+ret = ogGetCacheSpace()
+
+if ret is not None:
+    if   ret == True: sys.exit (0)
+    elif ret == False: sys.exit (1)
+    else: print (ret)