[Coverity 1666275] Dereference null return value in text_layout.c

If the function actually returns a null value, a null pointer dereference will occur.

In LayoutLine: Return value of function which returns null is dereferenced without checking (CWE-476)

       19. Condition i_last_run != p_paragraph->pi_run_ids[i_paragraph_index], taking true branch.
       29. Condition i_last_run != p_paragraph->pi_run_ids[i_paragraph_index], taking true branch.
       39. Condition i_last_run != p_paragraph->pi_run_ids[i_paragraph_index], taking true branch.
1227        if( i_last_run != p_paragraph->pi_run_ids[ i_paragraph_index ] )
1228        {
1229            i_last_run = p_paragraph->pi_run_ids[ i_paragraph_index ];
1230            p_run = p_paragraph->p_runs + i_last_run;
1231            p_style = p_run->p_style;
1232
1233            metrics.height_px = ConvertToLiveSize( p_filter, p_style );
1234            metrics.width_px = GetFontWidthForStyle( p_style, metrics.height_px );
1235
       40. returned_null: vlc_ftcache_LoadFaceByID returns NULL (checked 4 out of 5 times).[show details]
       41. var_assigned: Assigning: p_face = NULL return value from vlc_ftcache_LoadFaceByID.
1236            p_face = vlc_ftcache_LoadFaceByID( p_sys->ftcache, p_run->p_faceid, &metrics );
1237        }
1238
1239        FT_Vector pen_new = {
1240            .x = pen.x + p_paragraph->p_glyph_bitmaps[ i_paragraph_index ].i_x_offset,
1241            .y = pen.y + p_paragraph->p_glyph_bitmaps[ i_paragraph_index ].i_y_offset
1242        };
1243        FT_Vector pen_shadow = {
1244            .x = pen_new.x + p_sys->f_shadow_vector_x * ( metrics.width_px << 6 ),
1245            .y = pen_new.y + p_sys->f_shadow_vector_y * ( metrics.height_px << 6 )
1246        };
1247
1248        /* Shadow being a reference to main glyph, it must be processed first */
       20. Condition p_bitmaps->p_shadow, taking true branch.
       21. Condition FT_Glyph_To_Bitmap(&p_bitmaps->p_shadow, FT_RENDER_MODE_NORMAL, &pen_shadow, 0), taking true branch.
       30. Condition p_bitmaps->p_shadow, taking true branch.
       31. Condition FT_Glyph_To_Bitmap(&p_bitmaps->p_shadow, FT_RENDER_MODE_NORMAL, &pen_shadow, 0), taking true branch.
       42. Condition p_bitmaps->p_shadow, taking true branch.
       43. Condition FT_Glyph_To_Bitmap(&p_bitmaps->p_shadow, FT_RENDER_MODE_NORMAL, &pen_shadow, 0), taking true branch.
1249        if( p_bitmaps->p_shadow &&
1250            FT_Glyph_To_Bitmap( &p_bitmaps->p_shadow, FT_RENDER_MODE_NORMAL,
1251                                &pen_shadow, 0 ) )
1252        {
1253            p_bitmaps->p_shadow = 0;
1254        }
1255
1256        /* Ensure we don't release reference */
1257        FT_Glyph bitmapglyph = p_bitmaps->cglyph.p_glyph;
       22. Condition FT_Glyph_To_Bitmap(&bitmapglyph, FT_RENDER_MODE_NORMAL, &pen_new, 0), taking true branch.
       32. Condition FT_Glyph_To_Bitmap(&bitmapglyph, FT_RENDER_MODE_NORMAL, &pen_new, 0), taking true branch.
       44. Condition FT_Glyph_To_Bitmap(&bitmapglyph, FT_RENDER_MODE_NORMAL, &pen_new, 0), taking false branch.
1258        if( FT_Glyph_To_Bitmap( &bitmapglyph,
1259                                FT_RENDER_MODE_NORMAL,
1260                                &pen_new, 0 ) )
1261        {
1262            ReleaseGlyphBitMaps( p_filter, p_bitmaps );
       23. Continuing loop.
       33. Continuing loop.
1263            continue;
1264        }
1265
1266        /* release the source glyph or reference */
1267        vlc_ftcache_Glyph_Release( p_sys->ftcache, &p_bitmaps->cglyph );
1268        p_bitmaps->cglyph.p_glyph = bitmapglyph;
1269
       45. Condition p_bitmaps->coutline.p_glyph, taking true branch.
1270        if( p_bitmaps->coutline.p_glyph )
1271        {
1272            bitmapglyph = p_bitmaps->coutline.p_glyph;
       46. Condition FT_Glyph_To_Bitmap(&bitmapglyph, FT_RENDER_MODE_NORMAL, &pen_new, 0), taking true branch.
1273            if( FT_Glyph_To_Bitmap( &bitmapglyph,
1274                                    FT_RENDER_MODE_NORMAL,
1275                                    &pen_new, 0 ) )
1276                bitmapglyph = NULL;
1277            vlc_ftcache_Custom_Glyph_Release( &p_bitmaps->coutline );
1278            p_bitmaps->coutline.p_glyph = bitmapglyph;
1279        }
1280
1281        FT_Glyph_Get_CBox( p_bitmaps->cglyph.p_glyph, FT_GLYPH_BBOX_PIXELS,
1282                           &p_bitmaps->glyph_bbox );
1283        FixGlyph( p_bitmaps->cglyph.p_glyph, &p_bitmaps->glyph_bbox,
1284                  p_bitmaps->i_x_advance, p_bitmaps->i_y_advance,
1285                  &pen_new );
       47. Condition p_bitmaps->coutline.p_glyph, taking false branch.
1286        if( p_bitmaps->coutline.p_glyph )
1287        {
1288            FT_Glyph_Get_CBox( p_bitmaps->coutline.p_glyph, FT_GLYPH_BBOX_PIXELS,
1289                               &p_bitmaps->outline_bbox );
1290            FixGlyph( p_bitmaps->coutline.p_glyph, &p_bitmaps->outline_bbox,
1291                      p_bitmaps->i_x_advance, p_bitmaps->i_y_advance,
1292                      &pen_new );
1293        }
       48. Condition p_bitmaps->p_shadow, taking false branch.
1294        if( p_bitmaps->p_shadow )
1295        {
1296            FT_Glyph_Get_CBox( p_bitmaps->p_shadow, FT_GLYPH_BBOX_PIXELS,
1297                               &p_bitmaps->shadow_bbox );
1298            FixGlyph( p_bitmaps->p_shadow, &p_bitmaps->shadow_bbox,
1299                      p_bitmaps->i_x_advance, p_bitmaps->i_y_advance,
1300                      &pen_shadow );
1301        }
1302
1303        int i_line_offset    = 0;
1304        int i_line_thickness = 0;
1305
       49. Condition p_ch->p_style->i_style_flags & (96 /* (1 << 5) | (1 << 6) */), taking true branch.
1306        if( p_ch->p_style->i_style_flags & (STYLE_UNDERLINE | STYLE_STRIKEOUT) )
1307        {
      
CID 1666275: (#1 of 1): Dereference null return value (NULL_RETURNS)
50. dereference: Dereferencing p_face, which is known to be NULL.
       CID 1346944:Dereference after null check (FORWARD_NULL) [ "select issue" ]
1308            i_line_offset =
1309                labs( FT_FLOOR( FT_MulFix( p_face->underline_position,
1310                                           p_face->size->metrics.y_scale ) ) );