<p>lynxis lazus has uploaded this change for <strong>review</strong>.</p><p><a href="https://gerrit.osmocom.org/c/osmo-pcu/+/14481">View Change</a></p><pre style="font-family: monospace,monospace; white-space: pre-wrap;">decompress_crbb: add length argument for search_runlen<br><br>search_runlen() must know the exact size in bits when parsing<br>the bits otherwise it read over the buffer.<br>Fixes testcase #7 which was wrongly decoded.<br><br>Change-Id: Ie34a0651e7e7efea4e9ecff1e3a467588113cf47<br>---<br>M src/egprs_rlc_compression.cpp<br>M tests/bitcomp/BitcompTest.cpp<br>M tests/bitcomp/BitcompTest.err<br>3 files changed, 14 insertions(+), 14 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;">git pull ssh://gerrit.osmocom.org:29418/osmo-pcu refs/changes/81/14481/1</pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/src/egprs_rlc_compression.cpp b/src/egprs_rlc_compression.cpp</span><br><span>index 927c6cd..3972b21 100644</span><br><span>--- a/src/egprs_rlc_compression.cpp</span><br><span>+++ b/src/egprs_rlc_compression.cpp</span><br><span>@@ -449,6 +449,7 @@</span><br><span> /* Calculate runlength of a codeword</span><br><span> * \param root[in] Root of Ones or Zeros tree</span><br><span> * \param bmbuf[in] Received compressed bitmap buf</span><br><span style="color: hsl(120, 100%, 40%);">+ * \param length[in] Length of bitmap buf in bits</span><br><span> * \param bit_pos[in] The start bit pos to read codeword</span><br><span> * \param len_codewd[in] Length of code word</span><br><span> * \param rlen[out] Calculated run length</span><br><span>@@ -456,6 +457,7 @@</span><br><span> static int search_runlen(</span><br><span> egprs_compress_node *root,</span><br><span> const uint8_t *bmbuf,</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t length,</span><br><span> uint8_t bit_pos,</span><br><span> uint8_t *len_codewd,</span><br><span> uint16_t *rlen)</span><br><span>@@ -469,6 +471,9 @@</span><br><span> while (iter->run_length == -1) {</span><br><span> if ((!iter->left) && (!iter->right))</span><br><span> return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ if (bit_pos >= length)</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> /* get the bit value at the bitpos and put it in right most of dir */</span><br><span> dir = (bmbuf[bit_pos/8] >> (7 - (bit_pos & 0x07))) & 0x01;</span><br><span> bit_pos++;</span><br><span>@@ -498,7 +503,7 @@</span><br><span> const uint8_t *orig_crbb_buf,</span><br><span> bitvec *dest)</span><br><span> {</span><br><span style="color: hsl(0, 100%, 40%);">-</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t remaining_bmap_len = compress_bmap_len;</span><br><span> uint8_t bit_pos = 0;</span><br><span> uint8_t data;</span><br><span> egprs_compress_node *list = NULL;</span><br><span>@@ -509,7 +514,7 @@</span><br><span> int rc = 0;</span><br><span> egprs_compress *compress = instance();</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">- while (compress_bmap_len > 0) {</span><br><span style="color: hsl(120, 100%, 40%);">+ while (remaining_bmap_len > 0) {</span><br><span> if (start) {</span><br><span> data = 0xff;</span><br><span> list = compress->ones_list;</span><br><span>@@ -517,7 +522,7 @@</span><br><span> data = 0x00;</span><br><span> list = compress->zeros_list;</span><br><span> }</span><br><span style="color: hsl(0, 100%, 40%);">- rc = search_runlen(list, orig_crbb_buf,</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = search_runlen(list, orig_crbb_buf, compress_bmap_len,</span><br><span> bit_pos, &nbits, &run_length);</span><br><span> if (rc == -1)</span><br><span> return -1;</span><br><span>@@ -525,6 +530,7 @@</span><br><span> if (run_length < 64)</span><br><span> start = !start;</span><br><span> cbmaplen = cbmaplen + run_length;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> /* put run length of Ones in uncompressed bitmap */</span><br><span> while (run_length != 0) {</span><br><span> if (run_length > 8) {</span><br><span>@@ -536,7 +542,7 @@</span><br><span> }</span><br><span> }</span><br><span> bit_pos = bit_pos + nbits;</span><br><span style="color: hsl(0, 100%, 40%);">- compress_bmap_len = compress_bmap_len - nbits;</span><br><span style="color: hsl(120, 100%, 40%);">+ remaining_bmap_len = remaining_bmap_len - nbits;</span><br><span> }</span><br><span> return 0;</span><br><span> }</span><br><span>diff --git a/tests/bitcomp/BitcompTest.cpp b/tests/bitcomp/BitcompTest.cpp</span><br><span>index 29a8c15..ebdcf6f 100644</span><br><span>--- a/tests/bitcomp/BitcompTest.cpp</span><br><span>+++ b/tests/bitcomp/BitcompTest.cpp</span><br><span>@@ -91,14 +91,13 @@</span><br><span> .ucmp_len = 90,</span><br><span> .expect_rc = 0,</span><br><span> },</span><br><span style="color: hsl(0, 100%, 40%);">- /* TODO: previously marked as "Invalid inputs" but succeeds */</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Invalid inputs */</span><br><span> { .crbb_len = 18, .cc = 1,</span><br><span> .crbb_data = {0x1E, 0x70, 0xc0},</span><br><span> .ucmp_data = {0xb0, 0x00, 0x00},</span><br><span> .ucmp_len = 19,</span><br><span style="color: hsl(0, 100%, 40%);">- .expect_rc = 0,</span><br><span style="color: hsl(120, 100%, 40%);">+ .expect_rc = -1,</span><br><span> },</span><br><span style="color: hsl(0, 100%, 40%);">- /* Invalid inputs */</span><br><span> { .crbb_len = 14, .cc = 1,</span><br><span> .crbb_data = {0x00, 0x1E, 0x7c},</span><br><span> .ucmp_data = {0x0},</span><br><span>diff --git a/tests/bitcomp/BitcompTest.err b/tests/bitcomp/BitcompTest.err</span><br><span>index 2eabd78..2c4ed0a 100644</span><br><span>--- a/tests/bitcomp/BitcompTest.err</span><br><span>+++ b/tests/bitcomp/BitcompTest.err</span><br><span>@@ -108,13 +108,8 @@</span><br><span> Run_length = 1</span><br><span> Run_length = 1</span><br><span> Run_length = 2</span><br><span style="color: hsl(0, 100%, 40%);">-Run_length = 15</span><br><span style="color: hsl(0, 100%, 40%);">-rc = 0</span><br><span style="color: hsl(0, 100%, 40%);">-</span><br><span style="color: hsl(0, 100%, 40%);">-expected data = b0 00 00 </span><br><span style="color: hsl(0, 100%, 40%);">-expected len = 19</span><br><span style="color: hsl(0, 100%, 40%);">-decoded data = b0 00 00 </span><br><span style="color: hsl(0, 100%, 40%);">-decoded len = 19</span><br><span style="color: hsl(120, 100%, 40%);">+rc = -1</span><br><span style="color: hsl(120, 100%, 40%);">+Failed to decode CRBB: length 18, data 1e 70 c0 </span><br><span> </span><br><span> Test:8</span><br><span> Tree based decoding:</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/c/osmo-pcu/+/14481">change 14481</a>. 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<div style="display:none"> Gerrit-Project: osmo-pcu </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-Change-Id: Ie34a0651e7e7efea4e9ecff1e3a467588113cf47 </div>
<div style="display:none"> Gerrit-Change-Number: 14481 </div>
<div style="display:none"> Gerrit-PatchSet: 1 </div>
<div style="display:none"> Gerrit-Owner: lynxis lazus <lynxis@fe80.eu> </div>
<div style="display:none"> Gerrit-MessageType: newchange </div>